Microfinder Doppler Operator's Guide

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MicroFinder Doppler

Operator’s Guide

Version 2.0.2a September 13, 2000

INTRODUCTION ...... 1

DEFINITIONS...... 2

USER FEATURES ...... 3

MICROFINDER FRONT PANEL...... 4

CIRCUIT DESCRIPTION...... 5

SOFTWARE ARCHITECTURE...... 6

PROCESSES...... 6 BUTTON TABLE...... 7 COMMAND PROCESSOR ...... 10

MICROFINDER COMMANDS...... 10 MICROFINDER PARAMETERS ...... 12 USING CLI ...... 13 PHYSICAL CONFIGURATION...... 13

THE CALIBRATION PROCEDURE...... 14

INITIAL SETUP ...... 15 CALIBRATION...... 16 CALIBRATION SETUP...... 16 DIRECTION FINDING CALIBRATION...... 17 CONFIGURATIONS ...... 18 CALIBRATING WITH CONFIGURATIONS ...... 19 EXAMINING THE CONFIGURATION INFORMATION...... 20 COMPASS CALIBRATION ...... 20 SETTING MICROFINDER OPTIONS ...... 22 USING THE MICROFINDER ...... 23

BASIC DOPPLER OPERATION...... 23 ABSOLUTE DISPLAY...... 24 COMPASS DISPLAY...... 26

DISPLAY OPTIONS...... 26

MARGINAL SIGNALS...... 26

REFLECTION FILTERING ...... 27 INTERMITTENT TRANSMITTER FILTERING...... 28 LOSS OF SIGNAL...... 29 A WARNING ABOUT FILTERING...... 29 TRANSMITTED AUDIO INTERFERENCE ...... 29

OPERATION OF MICROFINDER WITH A GPS UNIT...... 30

OPERATION OF MICROFINDER WITH THE COMPUTER AND APRS...... 31

HALTING DOPPLER OPERATION DURING TRANSMIT ...... 31

AHHA! Solutions September 13, 2000 MicroFinder Operator's Guide Version 2.0.2a TROUBLE SHOOTING THE MICROFINDER...... 31

MICROFINDER ERROR MESSAGES ...... 33

COMMAND INTRODUCTION...... 36

ALARM (AL)...... 36 USER COMMANDS...... 37

ASW...... 37 BAUD (BA)...... 38 BEARING (BE)...... 38 BTAB (BT)...... 39 CHKANTENNA (CHK) ...... 39 COMPASS (COM)...... 40 HELP (?)...... 40 MYCALL (MY)...... 41 RESET ...... 41 SAVE...... 41 ADVANCED COMMANDS...... 42

ALARM (AL)...... 42 APRS...... 43 CALV (CA) ...... 44 CONFIG (CON) ...... 44 EXECBTN (EX) ...... 45 GPS ...... 45 OPT...... 46 PS ...... 46 QFILT...... 47 QUAL ...... 47 ROTATION (RO) ...... 48 RUN ...... 48 STOP ...... 48 DEBUG COMMANDS ...... 49

CCW...... 49 CW...... 50 EEDUMP (EED)...... 50 EEREAD (EER) ...... 51 EEWRITE (EEW) ...... 51 EEZERO (EEZ)...... 51 LEDTO (LED) ...... 52 RBYTE (RB)...... 52 RWORD (RW) ...... 52 SEG7...... 53 STEPTO (ST)...... 53 TIME (TI) ...... 53 WBYTE (WB)...... 54 WWORD (WW)...... 54 APPENDIX A - BUTTON FUNCTION CODES ...... 55 APPENDIX B - PROCESS ID CODES...... 56 APPENDIX C - EEPROM MEMORY MAP ...... 57 APPENDIX D - CPU RAM MAP ...... 58 AHHA! Solutions September 13, 2000 MicroFinder Operator's Guide Version 2.0.2a Introduction

This section of the MicroFinder User’s Guide describes the operational aspects of the MicroFinder. In other words, this is all the stuff you need to know after you have built the unit. You will find the basic information you need to use the doppler, as well as technical details such as the system hardware and software architecture (in case you are interested). The following sections are important: · Configuration · Calibration · Using the MicroFinder (in the hunt)

An assembled MicroFinder installed and ready to hunt. Photo courtesy of Jim Sakane KD6DX.

AHHA! Solutions 1 September 13, 2000 MicroFinder Operator's Guide Version 2.0.2a Definitions

The following terms are defined as a convenience: APRS™ 1 - “Amateur Position Reporting System” is a popular packet mode in Amateur Radio. The MicroFinder is designed with APRS compatibility. Doppler Bearing - The direction to the hidden transmitter. The bearing may be either relative to the vehicle or an absolute direction. Doppler Degrees - The MicroFinder measures angles in units of 1.8 degrees. Each of these units is called a “doppler degree.” EPROM - Erasable Programmable Read Only Memory. This is a form of PROM that can be erased and rewritten many times. Exposing them to UV light erases EPROM devices. EEPROM - Electrically Erasable Programmable Read Only Memory. This type of EPROM can be erased by an electrical pulse and can be rewritten while it is installed in the circuit. GPS - “Global Position System” is the satellite-based navigation system created by the U.S. Department of Defense. GPS receiver support is included in the MicroFinder system. GPS Data Pump - The MicroFinder includes a feature, called the “GPS Data Pump” that combines GPS and doppler data. This is used to simplify the connections between a computer and the MicroFinder. Hall Effect Compass - A solid state device, when connected to the MicroFinder that allows the doppler to calculate absolute bearing information. Magnetic Heading - The relative angle between the vehicle and North.

1APRS™ is a trademark of Bob Bruninga MacAPRS™ and WinAPRS™ are trademarks of Mark and Keith Sproul

AHHA! Solutions September 13, 2000 MicroFinder Operator's Guide 2 Version 2.0.2a User Features

The MicroFinder is a full-featured doppler and you will want to make sure you understand how everything works. Here is a brief summary of the features contained in the MicroFinder: · Multiple antenna configurations: 3, 4, 6, or 8 elements. Switch may be logic high or low. · Bearing information is displayed relative to vehicle, or absolute. · Built in filtering reject reflections and deals with intermittent transmitters. · Adjustable antenna rotation rates help defeat fox spoilers or transmitted audio interfering with doppler operation. · Built-in antenna tester checks the antenna switching system for integrity every time the MicroFinder is restarted. · Button functions are user-configurable. · Four buttons are built-in, with external capability for a total of eight buttons. · External display capability. · Microprocessor design is flexible and future software upgrades can provide more features. · A “no retune” design eliminates those pesky analog components that cause other dopplers to lose their calibration settings. · User extensions are possible; a magnetic compass and a “heads up” quick look display. · Mechanical pointer (option) makes for easy visibility in daylight. · APRS compatibility. · Built-in audio monitor so you can hear what the received signal sounds like. · Audio feedback to supply alarm tone for missing signal conditions, antenna error faults, and user feedback from button presses.

AHHA! Solutions September 13, 2000 MicroFinder Operator's Guide 3 Version 2.0.2a MicroFinder Front Panel

Mechanical Pointer Bearing Scale 7 Segement Display

Reset Switch

Button 1 Button 2 Micro Button 3 Finder Button 4

Labels

Figure 1 - The MicroFinder front panel

Figure 1 shows the front panel of the MicroFinder. The controls of the MicroFinder are as follows: · Mechanical Pointer - This is the stepper motor driven pointer. It is useful for seeing the bearing information in direct sunlight. · Bearing Scale - This scale reads 0 to 359 degrees. Your bearing and compass information will be read from this scale. · Reset Switch - If you need to restart the MicroFinder, this button will do it. · Buttons 1 - 4 - These buttons provide functionality to change the behavior of the MicroFinder. You may assign functions to each button. See the section “Software Architecture - Button Table” · Labels - These white boxes are available for you to write the name of your chosen functions on the cover. We recommend that you use a fine point permanent marker (such as Sharpie). You can remove your labels with an alcohol wipe. · Seven Segment Display - The seven-segment display is used to display different information to you while your doppler is in use. The main use of the display is to show the quality of the current doppler bearing. Figure 2 shows three states of the display. Quality levels are all measured on a scale of 0 to 9. When the display shows one bar, the actual quality level may be 1, 2, or 3. Two bars correspond to 4, 5, or 6. Three bars correspond to 7, 8, or 9. Quality levels of zero or less will turn on just the decimal point.

Figure 2 - Quality Bars for quality levels 1-3, 4-6, and 7-9

AHHA! Solutions September 13, 2000 MicroFinder Operator's Guide 4 Version 2.0.2a Circuit Description

Audio Input Audio Monitor

DC 2nd Harmonic H8/338 Antenna Microcontroller Driver J3 Fundamental DC

Zero Detector Stepper Stepper Driver Pointer 50 LED Ring Display 7 Segment Display

Figure 3- MicroFinder circuit block diagram

The microcontroller doppler uses a Hitachi H8-338 as the main brains of the system. The controller provides all timing required for the doppler circuits. The antenna rotation rate is coordinated with the clock for the audio filters. The audio from your radio is connected to two audio filters. The first filter passes the fundamental frequency generated by the switching of the antennas. The second filter passes the second harmonic frequency, which is generated when reflections are received. The output of the filters are rectified by IC3 and measured by the microcontroller. If the second harmonic is stronger than the fundamental, the doppler is detecting a reflection and the software can ignore it. IC4 is a zero-crossing detector that provides the bearing information to the controller. The controller drives the multiplexed LED display of 50 LEDs and the seven- segment display. This is also connected to J2 and can be connected to another remote LED display. The buttons are also connected through J2 and mounted in an external assembly with a display. J2 provides the RS 232 connection to your computer for testing, button assignment, direction information, and APRS interface. To use the RS 232 interface, please make up a cable using only pins 2, 3, and 7 to connect to the computer. More information is in the construction manual. J2 also supplies

AHHA! Solutions September 13, 2000 MicroFinder Operator's Guide 5 Version 2.0.2a several microprocessor controlled signals that may be used for future enhancements. The antenna driver connector J3 provides the current required to switch the antennas. The system can support 3, 4, 6, or 8 antennas and can drive active high switching (recommended) or active low switching (as used by the Roanoke doppler). The stepper motor pointer is driven by the controller using darlington transistors. The pointer is independent of the LED display and can display different information. The stepper motor is NOT supplied with the kit. These stepper motors are available in some 5.25-inch floppy disk drives. Look for them at your local swap meet. For the particular manufacturer's names and models see the parts list. The stepper motor performs 200 steps per revolution or 1.8 degree steps and has 5 or 6 separate leads.

Software architecture

The MicroFinder embedded software is contained in a PROM that is imbedded in the Hitachi microprocessor. The software coordinates multiple activities taking place on the doppler. Some examples of the these activities are: · Multiplexing the LED display, including the seven-segment display. · Controlling the action of the motorized pointer. · Scanning the buttons and executing the button functions. · Executing typed commands from the serial port. · Electrically rotating the antennas and coordinating them with hardware filters. · Saving and restoring the configuration parameters to non-volatile flash EEPROM (electrically erasable programmable read only memory). · Providing bearing information to a host computer. · Converting the hall effect compass signals into magnetic heading information. As you can see, the software has a lot of work to do. This section will describe how the software accomplishes all of these tasks. In order to do so, the overall architecture for the software is discussed. Some of the concepts in the section are important because they will affect how and what you control or configure in your MicroFinder.

Processes The main software routines that take care of basic operational functions are called processes. Each process has a single function that it manages. These processes are scheduled time in a round-robin fashion, which presents the appearance of simultaneous operation of many functions of the doppler. Processes are classified into two groups; driver and normal processes. Driver processes are defined as those processes that must never be stopped. If a driver process is stopped, proper functioning of the doppler will cease. Normal

AHHA! Solutions September 13, 2000 MicroFinder Operator's Guide 6 Version 2.0.2a processes may be stopped or started under certain circumstances to alter the behavior of the doppler. All processes in the system are described by a four- letter descriptor code called the “process id”. The following table lists all of the processes in the system:

Procedure Name Procedure ID Description Attractive Mode patt Fancy LED display to impress your friends Alarm palm Monitor signal loss, sound alarm when appropriate. Button Processor pbut Button input processor Doppler Pointer pdil Display bearing information on the pointer Doppler display pled Display bearing information on the LED ring APRS update psnp Send APRS compatible info through the RS-232 port Analog Driver danl Analog interface driver LED Driver dled LED multiplex driver Doppler Calibrate Driver dcal Doppler calibration driver Compass Calibrate Diver dcmp Compass calibration driver Serial input processor dser Receive serial input and execute commands Sound Driver dsnd Play tones for the sounder Serial Output dsop Print buffered output to RS-232 Stepper Motor Driver dstp Control the stepper motor for the pointer process.

Button Table

The four buttons installed in the doppler, including the four external buttons, were assigned default functions when the software was written. As a user configuration option, the functions on the buttons may be reassigned to suit your needs or options. To achieve this, there is a set of functions that may be assigned to any button. When the configuration of the doppler is saved to non- volatile storage, the button assignments are also saved. Each possible button

AHHA! Solutions September 13, 2000 MicroFinder Operator's Guide 7 Version 2.0.2a The following table lists all the button functions available for assignment:

Button Name Button ID Type Description APRS Bearing bapr Operation Send an APRS bearing through the RS-232 port Attract batt Operation Turn on the fancy LED display, impress your friends Accept bacc Maint Save the calibration values Calibration Calibrate bcal Maint Calibrate the doppler Doppler Check bchk Maint Check the antenna switch for Antenna proper operation Change bcfg Operation Change the currently active Configuration configuration Custom 1 bcf1 Extended Send the string “CB1” through the RS-232 port Custom 2 bcf2 Extended Send the string “CB2” through the RS-232 port Custom 3 bcf3 Extended Send the string “CB3” through the RS-232 port Custom 4 bcf4 Extended Send the string “CB4” through the RS-232 port Calibrate bcmp Maint Calibrate the hall effect Compass compass Dim the LED bdim Operation Dim the LED display to 25% of display normal intensity Filter bflt Operation Switch filtering from off, to quality, to quality + queue filter GPS Print bgps Operation Cause the last captured GPS sentence to be printed to the RS- 232 port Hold Display bhld Operation Hold the current bearing information on the display Filter the LED blpt Operation Low pass filter the LED display display to emulate the pointer Pointer Speed bptr Operation Change the pointer speed Pointer bpoo Operation Turn the pointer on or off On/Off Antenna Rate brat Operation Change the antenna rotation rate Bearing brng Operation Print he bearing to the RS-232 port

AHHA! Solutions September 13, 2000 MicroFinder Operator's Guide 8 Version 2.0.2a Snooper bsnp Operation Start the continuous display of the bearing information LED Switch bswt Operation Switch LED display between relative, absolute, & compass

There are three types of button functions: · Operations related functions are those buttons to be used while using the doppler to find a hidden transmitter. · Doppler maintenance functions are those to be used when setting up the doppler. · Extended button functions are used for custom user-defined purposes.

Operational button functions are bapr, batt, bcfg, bdim, bflt, bhld, blpt, bptr, bpoo, brat, brng, bsnp, and bswt. Because there is a wide mix of functionality, and relatively few buttons, you need to determine which functions will be most useful. We think the following best describes the utility of these buttons: · Generally useful: LED Switch (bswt), Filter ( bflt), Rate (brat), Pointer Speed (bptr), Low Pass filter LEDs (blpt), Change Configuration (bcfg), Dim the LEDs (bdim) · Useful for computer assistance (including APRS) Filter (bflt), APRS bearing (brng), APRS Continuous (bsnp), Send GPS Sentence (bgps) · Useful for intermittent transmitters Hold Display (bhld), LED Switch (bswt), Rate (brat), Pointer Speed (bptr)

Maintenance button functions are Calibrate Doppler (bcal), Calibrate Compass (bcmp), and Accept Calibrations (bacc). The functions are only used when you are calibrating your doppler. Normally you would not need to assign these functions to any buttons if you use the “deferred calibration” mechanism. You may, if you wish, permanently assign these to the buttons 6, 7, and 8. By building a small removable button box that plugs into the “Computer/AUX” connector on the doppler, you will be able to access these when you need to calibrate the unit. Figure 22 in the Construction Guide shows how to build this box. The antenna check function may be useful so it is available as a button. Assign the antenna check function (bchk) to the button of your choice. When executed it performs the same test function on the antenna as is done upon system startup (or reset).

AHHA! Solutions September 13, 2000 MicroFinder Operator's Guide 9 Version 2.0.2a Extended button functions are bcf1, bcf2, bcf3, and bcf4. These functions do nothing but print the a string on the serial output. Custom button 1 (bcf1) will print “CB1”, custom button 2 (bcf2) will print “CB2”, and so on. You can write a program for your computer that responds to these buttons. Write your program to monitor the serial data from the doppler. When it the strings “CB1”, “CB2”, etc. you can invoke some unique feature of your program. This makes it easier to control your program if you are unable to look at the computer screen or keyboard.

Default Button Assignments

1 brat Change the antenna rotation rate

2 bptr Change the pointer speed

3 bflt Switch bearing filtering to quality, quality+queue, or off

4 bhld Hold the current bearing information on the display

5 brng Send an APRS bearing to the RS-232 port

6 bcal Calibrate the doppler

7 bcmp Calibrate the hall effect compass

8 bacc Save the calibration values

Command Processor

When you interact with the doppler software, you will do so using a computer and terminal emulator program. Commands to the doppler are entered and executed upon pressing the return key. All commands are of the form: command argument(s) Each command must be spelled correctly, and there may be zero or more arguments. When the doppler can not understand your command, you will be informed with a response of “QSD!”. This is the doppler’s way of telling you the attempted command could not be executed. The “Command Reference” guide documents the parameters and usage of each command. Some commands can be abbreviated to a few characters. The command reference details allowable abbreviations for each command.

MicroFinder Commands

The MicroFinder provides several commands that may be used to configure and use the system. The commands are documented in detail in the “Command Reference Guide.” The following tables show the commands available. “User Commands” are the ones you will use most of the time to configure your doppler. “Advanced Commands” may be used to access

AHHA! Solutions September 13, 2000 MicroFinder Operator's Guide 10 Version 2.0.2a infrequently used functions or parameters. “Debug Commands” will only be used when you are building, debugging, or performing some maintenance function on the MicroFinder.

User Commands asw Set or show the antenna configuration baud Set or show the RS-232 baud rate bearing Show the current doppler bearing btab Set or show the button table assignments check Check the antenna switcher compass Show the compass heading help Print a short description of the MicroFinder commands mycall Set your call sign in the unit reset Restart the MicroFinder save Save the configuration into non-volatile memory

Advanced Commands aprs Set or show the APRS parameters alarm Set the alarm conditions calv Start the calibration process config Switch to and set configuration sets execbtn Execute a button function (for host computer use) gps Set the parameters for GPS capturing opt Enable or disable user supplied MicroFinder options ps Display the state MicroFinder software processes Adjust the parameters of the filtering queue for the second filter qfilt mode. qual Show the current bearing quality value rotation Set or show the antenna rotation rate run Resume the operation of a MicroFinder process stop Suspend the operation of a MicroFinder process

AHHA! Solutions September 13, 2000 MicroFinder Operator's Guide 11 Version 2.0.2a Debug Commands ccw Move the pointer display one step counter clockwise cw Move the pointer display one step clockwise eedump Display the raw contents of the non-volatile store eer Read one location of the non-volatile store eew Write one location of the non-volatile store eezero Erase the non-volatile store ledto Test the 50 LED ring display rb Read a byte from memory (RAM only) rw Read a word from memory (RAM only) seg7 Write a value (0-9,A-F) to the 7 segment display stepto Move the pointer display to a specific location time Show the amount of time the MicroFinder has been running wb Write a byte into memory (RAM only) ww Write a word into memory (RAM only)

MicroFinder Parameters

There is a set of parameters used by the MicroFinder to determine its behavior. These parameters are adjusted via the use of the CLI commands, and the parameter values are stored in the non-volatile memory. This section describes the parameters that you can adjust, what function they perform, and what command you will use to adjust it.

Parameter Use Command Description Alarm conditions alarm How long the signal must be missing in order to trigger the audio alarm Number of asw The number of antenna in the system antennas Antenna rate rotation The rate at which the antenna system rotates Antenna asw The logic level (low or high) and switching level voltage level used to switch the antennas (0.0 or 5.5 Volts) RS-232 baud rate baud The serial speed for communicating with the host computer Callsign mycall Your callsign, used as the CLI prompt. Compass option opt Allow the use of the optional

AHHA! Solutions September 13, 2000 MicroFinder Operator's Guide 12 Version 2.0.2a compass unit. APRS quality aprs Only send bearings of this minimum value to the APRS computer APRS delay aprs The amount of time between bearing reports to the APRS computer Quicklook option opt Allow the use of the optional quicklook display

Using CLI

Commands to the doppler are entered via the serial port and interpreted by the Command Line Interface, commonly known as a CLI. Because the serial input buffer is limited in length, you will not be able to enter very long lines of text. If you attempt to type more characters than the buffer will hold, the buffer will be dumped and the doppler will indicate it is ignoring the line by printing: *** Input Buffer Overflow All commands must be spelled correctly, but are not case sensitive. As an example, these two commands are will perform exactly the same function: asw 8 1 ASW 8 1 If you make a mistake in typing a command, the characters “delete” (DEL) or “backspace” (BS) will erase the character just entered. You can erase further characters back to the start of the input line. Control X (^X) will cancel the whole line. For any commands you need to repeat, typing the command Control R (^R) will reissue the last command you typed in. If the last command you typed in was in error, the erroneous command will be reissued.

There is no inline editing of commands in the CLI beyond those functions supplied by ^R, ^X, or delete.

Physical Configuration

The MicroFinder doppler contains an embedded microprocessor. It is a fact of nature that square wave signals, used by all digital circuits, will radiate harmonics. The MicroFinder has been designed to minimize the interference with nearby radios and scanners. Despite all careful design work, harmonics do exist, and if you are not careful, you could cause interference with the radio delivering the audio to your doppler. The best way to avoid the interference with your scanner or radio is to keep them separated. While we can not guarantee that this will work (it usually does), mounting the doppler directly on top or directly underneath your

AHHA! Solutions September 13, 2000 MicroFinder Operator's Guide 13 Version 2.0.2a receiver will cause interference of some sort. We cannot predict where or what form the interference will take, but Mr. Murphy tells us it will be probably be on your fox frequency. Sometimes automobile power is “dirty”. If you examine this “pure DC” voltage on an oscilloscope, you would find lots of little spikes and wiggles. These fluctuations can generate false readings in your system. Sometimes the auto noise can enter through the receiver, sometimes it can enter in the doppler itself. If you appear to have this problem, you may need to get a “choke kit” to clean up your power. To reduce interference: · Mount the receiver and doppler apart as far is possible. · Route signal cables for the compass and antenna switch away from the receiver. · Make sure the power from your power supply or vehicle is free of spikes and noise.

The Calibration Procedure

Calibration is the most important procedure you will perform to make your MicroFinder operational. If the calibration procedure is successful, you should not have to recalibrate unless you make changes to the configuration. You will need to recalibrate your MicroFinder if: · The antenna is modified or changed · A different radio receiver is used · The compass is modified · You change your vehicle (size of the ground plane) · You would like to change any of the configurations If the antenna or compass is rotated from the configuration in which it was originally calibrated, you will need to recalibrate. The entire calibration procedure will take you 30 minutes or less. The first time you calibrate the MicroFinder, you should allocate more time since you may wish to restart the procedure.

AHHA! Solutions September 13, 2000 MicroFinder Operator's Guide 14 Version 2.0.2a Initial setup

The initial setup procedure will prepare the MicroFinder for the rest of the calibration. This procedure configures the unit for options, antenna configuration, and the computer connection. · Hook your MicroFinder to an RS-232 port of your computer. · Configure your computer serial port for the following parameters: · 4800 baud · 8 data bits · 1 start bit · no parity · no handshake

· The MicroFinder defaults to 4800 baud. If you wish, change this now with the “baud” command. If you will be using a GPS unit in your configuration, it is best to leave the rate at 4800, since most GPS units interface at 4800 baud. Don’t forget to change your terminal software speed in order to continue.

· If you will be attaching AHHA’s compass to your MicroFinder, use the command: opt +c This allows the MicroFinder to use the compass, and enables the compass functions. Without the compass, the MicroFinder will not be able display absolute bearings.

· If you will be attaching the quick look LED pack to your doppler, use the command; opt +q This allows the MicroFinder to utilize the “quick look” option.

NOTE: If you do not perform steps 3 & 4, you will not be able to use these features. The quick look option uses microprocessor connections that may be used for future enhancements. The quick look option may be incompatible these future enhancements.

· Adjust the antenna settings to match your antenna using the “asw” command. To properly set the antenna configuration, you will need to know · How many elements does your antenna system have (you can count them)? · Do the antenna elements switch “high” (+5 Volts) or “low” (0 Volts)?

AHHA! Solutions September 13, 2000 MicroFinder Operator's Guide 15 Version 2.0.2a Valid antenna configuration settings are: asw 3 l asw 3 h asw 4 l asw 4 h asw 6 l asw 6 h asw 8 l asw 8 h The command “asw” takes two arguments. The first argument is the number of antenna elements. The second argument indicates the switching level the processor will use: l = switch low or ground, h = switch high or +5 volts.

· Use the command “save” to store these settings in the non-volatile memory.

Calibration

There are two ways you can calibrate your MicroFinder. Perhaps the easiest is by taking a portable computer out to your vehicle. For users without portable computers (or terminals), the MicroFinder has a deferred calibration option available. In all cases you will need the following to calibrate the direction finding capabilities of your MicroFinder: · A fox box (the “hidden” transmitter), or a friend with an HT. · Your MicroFinder connected to the antenna and receiver. · The complete system installed in your vehicle of choice. · The compass correctly hooked up (if you have the compass option).

Calibration Setup

This procedure will assist you in setting up for calibration process2. · Hook your MicroFinder to your computer and power up the MicroFinder.

· The MicroFinder will display the start up banner.

· Issue the command “calv -”. This will place the MicroFinder into the calibration mode. Calibration mode will redefine buttons #1, #2 , and #3 to be assigned to “calibrate”, “calibrate compass”, “save calibration” respectively.

· If you are going to be calibrating a compass, issue the commands: dop> btab 4 bswt dop> eesave

2If you have a portable computer you may take it into the vehicle with you and use the command interface to assist you in calibrating your doppler.

AHHA! Solutions September 13, 2000 MicroFinder Operator's Guide 16 Version 2.0.2a You will want to use this button function to switch to the compass mode to check that the compass calibration appears to be correct.

The remainder of this procedure will take you through the calibration process. The first step is calibrating the direction finding capabilities. The second step will help you calibrate your compass (if you have it). At the end of each section, the calibration information is saved into the non-volatile memory inside the MicroFinder.

Direction Finding Calibration

Here it is, the direction finding calibration procedure. This portion of the process is the part that actually gets your MicroFinder oriented. When the calibration settings are saved, at the end of the process, you should not have to repeat this procedure unless changes are made to the doppler-antenna-receiver configuration. · Turn on the MicroFinder and receiver (tuned to your fox frequency). If the fox is transmitting and the receiver is tuned correctly to the fox’s frequency and the doppler is showing one constant direction, adjust the volume of the receiver just past 3 full bars on the quality display. Note: The volume level will change your calibration, so you should note the volume level at this point so you can restore the same setting the next time you use the equipment.

· If the fox is not turned on, the MicroFinder’s LED display will be displaying directions at random. If the LED display is not displaying random directions, check that your radio receiver is configured to produce the enough audio to drive the doppler. The receiver must have the squelch “open”, and the volume must be turned up, about 50 percent.

· Turn on your fox. Remember to follow FCC Part 97 rules and ID when required. While part 97 also specifies using lowest power required, it is a good idea to use about 0.5 Watt when calibrating. This will provide a reasonably strong signal for calibration without surrounding you with reflections.

· With the fox turned on, the MicroFinder should be displaying a relatively steady bearing, although it may not point directly at the transmitter.

· Position your vehicle until the fox is directly in front of the vehicle. This works best if you are at least one hundred feet from the transmitter. A small error now will be magnified later when the transmitter is farther away!

AHHA! Solutions September 13, 2000 MicroFinder Operator's Guide 17 Version 2.0.2a Fox Box

Figure 5 - Pointing your vehicle at the fox.

· When you have the transmitter “in your sights” and the quality display is showing “3 bars”, press the calibrate button. The MicroFinder begins calibrating each of the antenna rotation rates. At each rate it will display the rate number on the MicroFinder 7 segment display.

· When calibration is complete, the MicroFinder will return the seven- segment display to the normal “quality” display.

· Drive your vehicle around the transmitter, noting the bearing information from the MicroFinder. Make sure the bearings are accurate. If they are not, repeat steps 5 - 8 until satisfactory results are obtained.

· If you are going to calibrate a compass, proceed to the next section on “Compass Calibration.” If you have no compass and you are satisfied with the calibration, press the accept button. This will cause the doppler to save the calibration information to the non-volatile memory.

Configurations The MicroFinder calibration is affected by several variables: · Radio calibration values · Antenna configuration including the number of elements and the switching logic level · Antenna orientation. · Operating significantly away from the frequency at which the system was originally calibrated. Some hunters want to be able to use spare radios or build antennas that can be switched from 2 meters to 70 centimeters. The MicroFinder has the ability to store different sets of information sufficient to operate the MicroFinder. The information set is called a “configuration.” When you want to change one of the key aspects of your system, you can change to a new configuration, enabling your system to work properly.

AHHA! Solutions September 13, 2000 MicroFinder Operator's Guide 18 Version 2.0.2a When the MicroFinder is first initialized it is configured for a single configuration. This is sufficient for most MicroFinder users, but occasionally you may wish configure your MicroFinder system differently. In this case you are able to create a new configuration to hold your calibration values. To use configurations the MicroFinder supplies you two ways to select and modify configurations. You may select a new configuration to be “in use” (AKA “current”) using a button. The button function “bcfg” selects the new configuration. When the new configuration is selected, the seven-segment display will show “c#”, where “#” is the configuration set to be made current. The “config” command may also be used to select the current configuration as well as enable configurations (AKA “active”). Calibrating with Configurations Before you will be able to use a configuration, you will need to calibrate the configuration. This process is the same as previously described, except that you must select which configuration is “current”. Assume, for example, that you wish to calibrate a configuration set for a spare radio. The following process describes how set up your MicroFinder. · Configure the MicroFinder as previously described. · Make sure the configuration information is saved using either the “save” command or the “accept” button. · Turn off the MicroFinder power and reconfigure the hardware of your system (radios, antennas, etc.) · Connect the MicroFinder to your computer and apply power. · Using the configure command, set the new configuration to be current. As an example, assume that you want to make configuration #2 active as well as “current”: config 2 · Save the configuration in order to save the current configuration setting. · Select deferred calibration. · Set up your MicroFinder system and calibrate it as previously described. · Save your calibrated values using either the “save” command or the “accept” button.

Once you have created your new configuration, make the most common configuration “active” using either the “config” command or “bcfg” button. You then should save this setting. If at any time you want to enable the other configuration, make it active using the “bcfg” button or “config” command. At a later time you may determine that you no longer want a configuration to be active. Inactive configurations can not be used by selecting them with the “bcfg” button. To disable a configuration, use the “config” command. As an example, assume you want to disable configuration set #3: config –3 This will make configuration set inactive. You will always have one configuration active at all times.

AHHA! Solutions September 13, 2000 MicroFinder Operator's Guide 19 Version 2.0.2a Examining the Configuration Information At times you will want to look at the information stored for each of the configurations in your MicroFinder. You will use the "config" command to do this. Using only the command, without arguments, will print all of the configuration information:

This example shows two active configurations, #1 and #2. Configuration two is the current configuration. This means when the MicroFinder starts, assuming these configurations are saved, you must have a 6-element antenna (switched low) connected to the system. When you change configuration information such as the antenna configuration, the MicroFinder will display the same information for the current configuration only. This applies to the commands "asw" and "calv". Compass Calibration

For this procedure you need an accurate magnetic compass (or two roads that run North-South and East-West), and some method of marking directions. You will be positioning the vehicle to point in each of the four cardinal compass directions. This allows the MicroFinder to calibrate the readings from the geomagnetic sensor. · Lay out the compass lines on the ground, or find two intersecting streets that are aligned North-South and East-West. REMEMBER, you probably want to use “True North”, not magnetic north since most maps are oriented towards True North. Magnetic North will vary by several degrees, and it will be different depending on where in the world you are. Because of this, you may need to recalibrate your compass if you move your MicroFinder very long distance. True North Magnetic North

Figure 6 - The difference between True and Magnetic North

AHHA! Solutions September 13, 2000 MicroFinder Operator's Guide 20 Version 2.0.2a · Press the Compass Calibrate button on the MicroFinder. The 7 segment display will display the pattern of “ ”. This tells you to begin calibrating the compass.

· Drive your vehicle around in a circle at least two times. Take at least 30 seconds to do each turn. This lets the MicroFinder detect the voltage ranges of your sensor.

· When you have completed two circles, wait for 5 seconds, then press the compass button again. Now the MicroFinder displays “ ”, which tells you to point your vehicle north. If you have laid out the lines, you can sight them down the center of your hood. A better way is to have your friend outside, assisting your driving by directing you until you are parallel with the North-South line.

True North Magnetic North

Figure 7 - Aligning your vehicle with True North

· When you are aligned with the North-South line, wait 5 seconds, then press the compass button.

The MicroFinder now displays “ ”. Point your vehicle East and press the button. · When the MicroFinder displays “ ”, point your vehicle South, wait 5 seconds, then press the button.

· When the MicroFinder displays “ ”, point your vehicle West, wait 5 seconds, then press the button.

· You have completed the compass calibration. It is time to check your compass.

9) Press the LED switch button (assigned to button #4 at the beginning or this procedure) until the seven-segment display shows “C”. Drive

AHHA! Solutions September 13, 2000 MicroFinder Operator's Guide 21 Version 2.0.2a around checking the LED circle. The calibration is successful if the LED circle correctly shows the direction the vehicle is pointing. Note: If the display shows “C.”, you will need to restart the compass calibration process at step #2.

If the LED circle display “jumps” while performing step #9, you may have the two compass channels swapped from what the MicroFinder requires. See the trouble shooting section.

10) When you are satisfied, press the “accept” button. This will store all of the calibration values into the non-volatile memory.

IMPORTANT: when you press the “accept” button, buttons 1, 2, and 3 are no longer assigned to calibrate functions and they will revert to their previous assignments. If you need to recalibrate, you will need to reissue the “calv” command, which means a trip back to your computer. (Notebook computers are really inexpensive these days, you should really get one. Go to your local swap meet!)

Setting MicroFinder Options The MicroFinder supports various options in software and hardware. Most of the options will default to reasonable values. Depending upon how you want to use your MicroFinder you may wish to turn on, or off, some of the options.

MicroFinder Options Option code Meaning Default Default 1.X 2.X Compass C Enables the use of the Off Off hardware compass Dim LEDs D If on runs the LEDs at 25% of Off Off normal intensity GPS Streaming G Allows GPS information to Off Off passthrough without capture QuickLook Q Enables use of the Quicklook Off Off optional display Startup Tone T Plays health tune at startup Off On Button Click K Sounds a short beep when Off On buttons are pressed Pointer P Enables or disables the On On pointer functionality

Options may be turned on or off using the "opt" command. By preceding the option letter with a "+" an option is enabled. When preceding an option letter with a "-" the option is enabled. Example: opt +c enables the use of the compass opt -k disabled the button feedback

AHHA! Solutions September 13, 2000 MicroFinder Operator's Guide 22 Version 2.0.2a Using the command "opt" with no arguments will show the current settings of the options. In order to save options, you must "save" the MicroFinder settings. For more information on individual options you may need to refer to other sections of the MicroFinder manuals: · Compass - The optional compass hardware is described in the MicroFinder construction manual, and use of the compass id described in this manual (see the section on calibration and the section on the LED display). · Dim LEDs - Using the button "bdim" (or by enabling this option with "opt") the red LEDs will be dimmed to approximately 25% of their normal intensity. This is useful for operating at nighttime. · GPS Streaming – The previous version of the MicroFinder embedded software treated GPS data differently than the new version. Version 1.X software echoes GPS sentences to the serial output. With version 2.X the software will capture specified GPS sentences (see the section about advanced GPS operation). Should you require backward compatibility this option may be disabled. · Quicklook – If you have constructed the 3 LED Quicklook device (see the MicroFinder Construction Manual), you must enable this option in order to be able to use the display. · Startup Tone – The antenna test routine checks the antenna switch at startup. If the switch tests OK a rising tone is played on the sounder or a falling tone if the switch test fails. Disabling this option prevents the tones from sounding upon startup. · Button Click – Whenever buttons are pressed, the MicroFinder will sound a short blip on the sounder. Disabling this option will prevent button clicks. · Pointer – If you have not installed a stepper motor to drive the pointer you should disable this option. Doing so will free CPU time for other tasks.

Using the MicroFinder There are many uses for, and ways to use, the MicroFinder. This section will explain how the MicroFinder typically is used. Most MicroFinder users will be doing either Hidden Transmitter Hunting, or they might be hunting for jammers and other forms of RFI. However you will use your MicroFinder, you will want to make sure you understand the basic operation of the unit. This will allow you to get the most utility from your doppler, and have a good time doing it.

Basic Doppler Operation

The most basic use of the MicroFinder is the “relative bearing mode.” This is when the MicroFinder will display the hidden transmitter bearing relative to the front of the vehicle. A relative bearing may be visualized by imagining that

AHHA! Solutions September 13, 2000 MicroFinder Operator's Guide 23 Version 2.0.2a directly in front of you, and 180 degree position is directly behind you. Figure 8 shows an example of a relative bearing.

Direction of travel Direction to transmitter

❇

Micro Finder

Figure 8 - Relative bearing display

Relative bearings are most useful when you are close to the transmitter or you do not have time to stop and plot bearings on a map. Use of the relative bearing mode will let you “drive the bearing.” This means you drive your vehicle, using the doppler display to tell you where to steer. Driving your vehicle to follow the doppler display works well under strong- signal, low-noise conditions. However, reality has a way of intruding, as is often the case. What you will usually see is one of several things:

· Several LEDs, covering as many as 20 degrees, could be lit. · The bearing will shift rapidly while you drive · There may appear to be no bearing at all If you have marginal signals, and as a result a marginal bearing, there are other techniques you will need to use. See the section “Marginal Signals.”

Absolute Display

If you have installed the compass option, you will be able to display bearing information in an absolute manner. Absolute bearings are directions to the transmitter, relative to the direction North. Because an absolute bearing is relative to North, you can not easily use it to “drive the doppler.” This mode is best used when plotting bearings on a map. If you know your location, you can plot the bearing without having to do the vector math in your head, because the doppler has done it for you.

AHHA! Solutions September 13, 2000 MicroFinder Operator's Guide 24 Version 2.0.2a No matter which direction you turn your vehicle, the same bearing is displayed on the doppler display. Figure 9 shows two possible vehicle orientations, and the resulting absolute bearing on the doppler.

Direction North of travel

Direction of travel

Car #2

Car #1 Direction to transmitter

❇ Micro Finder

Figure 9 - Absolute bearing display

In Figure 9, two vehicles are shown in two different orientations. If you are in car #1 and are in relative mode, you will see a bearing of 180 degrees. Switching to absolute mode, you will see a bearing of 135. If you now turn your vehicle to match the orientation of car #2 (do not change location, just turn), your relative bearing will change to 90 degrees. When you switch to absolute mode, you will still see 135 degrees. The absolute bearing can easily be plotted on the map. You can turn on absolute mode by pressing the “Display Switch” (button function “bswt”). Because of the possibility for confusion between relative and absolute bearing mode, the doppler will display an “ ”on the seven segment display. This symbol will tell you that the bearing information you are seeing is absolute. Absolute mode is subject to the same marginal signal conditions as relative mode. See the section “Marginal Signals” for more information.

AHHA! Solutions September 13, 2000 MicroFinder Operator's Guide 25 Version 2.0.2a Compass Display

A doppler equipped with the compass has the ability to display the magnetic heading of your vehicle. The “Display Switch” button (button function “bswt”) will switch your display between relative, absolute, or compass functions. When you display the compass, the seven segment display will show “ ” to warn you that the LEDs and pointer are showing a magnetic heading not the bearing to the transmitter.

Display Options You may modify the LED (and pointer) display in several ways to suit your needs. Some display options will affect how the signal is interpreted while others do not. · Dim – Using the button function “bdim” or the option “opt +d” the red LEDs will be dimmed to 25% normal intensity. Note that this doesn’t affect the green back lighting LEDs for the pointer. · Hold – Using the button function “bhld” you can cause the display to “freeze” momentarily. This may be useful in high noise situations where you want to slow things down and think about the bearing. · Slow down the LED circle – Using the button function “blpt” the LED circle can be made to mimic the stepper motor pointer. This is the same as low pass filtering the signal and is useful for people without pointers. The LED display supports 5 rotation speeds, with the default being “0”, the fastest. Except for the “hold” setting, these settings are saved when the configuration is stored using the “save” command.

Marginal Signals

If you have ever been hunting a hidden transmitter, you know what we mean when we speak of marginal signals. If you have never been transmitter hunting, you will find out! Marginal signals are usually due to reflection, signal loss, or low power transmitters. During a conventional transmitter hunt, reflections and intermittent signal loss are the major problems. When hunting jammers, intermittent transmitters will likely be the major problem. The MicroFinder has been designed to work correctly in either of these degraded conditions. The MicroFinder provides two filtering options to improve operation under these marginal conditions: · Filter 1 - Reject signals that contain strong reflections · Filter 2 - Automatically capture and hold intermittent transmitters. You can turn these filters on by pressing the filter button (the buttons assigned

AHHA! Solutions September 13, 2000 MicroFinder Operator's Guide 26 Version 2.0.2a to the function “bflt”). The first time the button is pressed, you are using filter 1. The second time you press the button, you are using the filter 2. The seven segment display will tell you which mode you are in by displaying “ ” for filter 1, and displaying “ ” for filter 2. The third time you press the button, all filtering is turned off. When using filter 2 you need to adjust your radio with the squelch "just closed."

No Filtering Filter 1 Filter 2

Figure 10 - Turning on filtering with the filter button.

Reflection Filtering

Filter 1 is most useful when you are dealing with a strong transmitter and you have reflections. When the doppler hears two signals, it detects this as a reflection and will not display erroneous bearings. Figure 11 shows a reflection that can be rejected.

reflection

Fox Box direct signal

Figure 11 - A reflection that can be rejected

AHHA! Solutions September 13, 2000 MicroFinder Operator's Guide 27 Version 2.0.2a reflection

Fox Box

direct signal blocked

Figure 12 - A reflection that cannot be rejected.

If the doppler hears only one signal, and it happens to be a reflection, the doppler cannot tell if it is a reflection or not, and the bearing will be displayed. The scenario in figure 12 can not be filtered for rejections. Because the signal path allows only one strong signal to the doppler, the system cannot distinguish between this case and the case where a transmitter is at the upper mountain. As always, use experience and intelligence to provide the ultimate filter! The filters are parameterized and allow you to make adjustments to suit your tastes and conditions. We have adjusted the filters to operate the best that we can, but we admit that there might be better settings for various parameters. Should you adjust one of these filters to operate more effectively, please let us know. For more information on filter adjustment, see the section “Tuning your MicroFinder.”

Intermittent Transmitter Filtering

When dealing with a jammer or a “challenge” hunt with an intermittent transmitter, you need some way of capturing only the signal that interests you. The MicroFinder provides a basic “hold” button (button function “bhld”). This will stop the display from changing and is useful when your quarry comes on the air. This is simple and effective in many cases and will give you time to think about your bearing. Filter 2 will provide more advanced filtering for intermittent transmitters by utilizing the transmission history and quality of the signal. Because the operation of the filter is automatic, you do not have to pay close attention to the doppler as you are moving about. To increase the effectiveness of filter 2, you should adjust the squelch on your radio so no audio is heard when there is no signal. This will prevent erroneous readings from appearing on the display.

AHHA! Solutions September 13, 2000 MicroFinder Operator's Guide 28 Version 2.0.2a Loss of Signal

While filter 2 is in operation, if a good quality strong signal is present, the display will be updated continuously. When the signal strength diminishes or the quality diminishes, the doppler will continue to display the last known good bearing, but will blink the LED. This blinking is to alert you to the fact that the doppler is not hearing a “good enough signal” to determine a bearing. Using the “alarm” command you can set an alarm threshold. If the signal has been absent for longer than the number of seconds set with the alarm command, the MicroFinder will sound an alarm tone using the sounder. The actual alarm tone is three short beeps. The alarm sound will continue to sound at the specified time interval until the signal returns, or the MicroFinder is switched out of filter 2 mode. You may disable the alarm by setting the time interval to zero seconds. If your location has not changed since the signal dropped out, this bearing is still as accurate as when it was taken. This can happen if the transmitter turns off. If you are moving at 60 MPH and the LED has been blinking for 1 minute, the bearing should be considered inaccurate and disregarded. Experience will teach you how best to interpret the filtered bearings.

A Warning About Filtering

Because filters are designed to reduce the amount of information in a signal (lose the bad, keep the good), you will not be getting updates as quickly. In order to throw away more bad info and keep more good information, each filter is less sensitive than the preceding one. Filter 1 requires more signal than no filtering, and filter 2 requires more signal than filter 1.

Sometimes you may find yourself in situations with almost no signal at all. In cases such as these, you may find it is easier to run with no filtering at all.

Transmitted Audio Interference

All doppler units operate by switching the antenna array on and off in sequence. This sequence induces a tone in the discriminator of your radio. Some Fox boxes have transmit an audio tone close to the doppler rotation rate, designed to produce erroneous bearings and confuse the hunters. The MicroFinder has been designed to defeat this technique. If a transmitter is sending audio that is causing bad bearings, you can change the antenna rotation rate, and eliminate the tone transmitted by the fox. The rate button is used to change the antenna rate (button function “brat”). There are five rates available. When you change, the seven-segment display will show 1 - 5. Rates are about 200 Hz to 600 Hz. The doppler was calibrated for all 5 rates, and aside from a small jump when you change rates, the bearing information will be the same for all rates. We have found that some antenna rates tend to be more useful in high

AHHA! Solutions September 13, 2000 MicroFinder Operator's Guide 29 Version 2.0.2a reflection conditions, and some tend to be worse. The default value for the rate is #3, and seems to be the best. Feel free to experiment.

Operation of MicroFinder with a GPS unit

If you are intending to use your doppler with a GPS unit, you may take advantage of the built-in GPS capabilities. This functionality will reduce the serial port requirement on your laptop by combining the GPS NMEA data stream with the doppler bearing information into a single serial port. APRS, MacAPRS, and WinAPRS all make use of this feature. Because there will be times you want to enter commands into the doppler, the computer will need to send serial data to the doppler. One solution is to construct a cable for your GPS and computer configuration, and another cable for your computer configuration. Another way to do this is to build a cable with a switch in line. Figure 13 shows how the in-line switch cable might be done.

Doppler serial in GPS

Micro Doppler serial out Finder

Laptop

Figure 13 - One possible way to connect your GPS and computer to the MicroFinder

The MicroFinder is designed to watch the GPS data and capture specified sentences (see the “gps” command). When requested via button function “bgps” the MicroFinder will print the last captured GPS sentence. This allows computer programs to get the latest GPS data when it needs it. In order to do this, the computer running the program must be able to electronically switch button lines in order to utilize this functionality.

AHHA! Solutions September 13, 2000 MicroFinder Operator's Guide 30 Version 2.0.2a For programs that are unable to utilize the captured GPS information by switching the buttons, they may be able to use the GPS streaming mode. By enabling the “g” option the MicroFinder will enable streaming of all GPS data to the serial output. The bearing information will be interspersed with the GPS data. When MicroFinder is streaming the GPS data to the computer, it will take some processing time from other tasks. As a result you may notice that the seven- segment display “pulses” slightly. The effect is very slight and expected behavior. None of the other critical functions of the doppler are affected.

Operation of MicroFinder with the computer and APRS

Most DF compatible programs can accepts the bearing strings sent by the MicroFinder. For older, or non-compliant, programs you can switch the MicroFinder into a more compatible mode.3 Opt +0 This will modify the MicroFinder bearing output information to be compatible. The difference is that there is no tenths of a degree, and there is no absolute bearing information, if you have a compass. For example, if the bearing is 181.6, and your vehicle is pointed East, the normal bearing output will be: %181.6/6%271.6 When the compatible mode is enabled, the bearing is printed as: %181/6 This option has no effect on any other operation or display of the compass.

Halting Doppler Operation During Transmit When a doppler is operating nearby a transmitter it often induces a tone in your transmitted signal. This could give away the fact that your are using DF gear and at the very least it can be annoying to those listening to your signal. The MicroFinder supplies a signal wire that will allow you to disable the operation of the MicroFinder. You can connect the PTT lead from your rig to this signal line. When you transmit the MicroFinder will enter hold mode and stop rotation of the antenna. This will prevent the tone from being heard on your transmission. See the MicroFinder Construction Guide for more information.

Trouble shooting the MicroFinder

Symptom Possible Solution Power is not reaching the doppler. No display or no LEDs are lit Check the power connections or inline fuses.

3 At the time this is written the MicroFinder is compatible with DosAPRS, Win/MacAprs, and GPSS

AHHA! Solutions September 13, 2000 MicroFinder Operator's Guide 31 Version 2.0.2a Check the audio connection to the receiver, make sure the volume is The LED ring does not change sufficient, and the squelch is not engaged. Saved configuration values appear Reset configuration and save corrupted configuration again. Verify the computer interface cable is correct and the computer is using the correct communication parameters (default values are 4800-8-1-none) The computer can not communicate with the MicroFinder Verify that the serial port is configured for 4800-8-1-none and NO handshake. (handshake usually prevents the doppler from receiving the characters that you type) The MicroFinder is indicating that it has lost the signal. This occurs when you are using the second filter mode The MicroFinder beeps several ("F." mode) and there is no signal. times, every few seconds. Remove the MicroFinder from filter mode using the filter button function, or disable the alarm using the "alarm" command. The MicroFinder makes this The button "click" option is turned on. annoying beep every time I push a To turn it off, use the "opt -k" button. command. Press and hold one of the four front “I have no idea what the saved panel buttons while resetting the unit. parameters are, and the This temporarily restores all MicroFinder will not communicate MicroFinder configuration parameters with my computer” to factory defaults. The volume level on your receiver is The LEDs spin when the fox Ids too high. Adjust the volume so you just (or other audio tone is present), get 3 quality bars when receiving a regardless of rotation rate. clean signal. • Make sure the antenna control is connected • Make sure the audio is connected • Check the connections in your The Unit does not point correctly antenna switch and antenna array. (Appendix A of the construction guide shows you how to do this. • Your ground plane may not be symmetric.

AHHA! Solutions September 13, 2000 MicroFinder Operator's Guide 32 Version 2.0.2a MicroFinder Error Messages

The MicroFinder will display error messages appropriate to the operation you were trying to perform. Based upon the message, you will be required to take action to correct the situation in order to accomplish your goal. This section will help you interpret the messages, and provide guidance to correct the problem.

Error Message Description

Bad button number MicroFinder buttons are numbers 1-8 Bad hex number A MicroFinder command parameter was required to be a hex number. Use only the digits 0-9 and a-f to specify a hex number Bad function specification An unknown button function was specified. Use “Appendix A” of the Command Reference Guide to choose an available function code. Bad number A MicroFinder command parameter was required to be a number. Use only the digits 0-9 to specify a decimal number. *** Canceled You typed Control-X, which cause the doppler to reset the input command buffer. EEPROM empty The EEPROM does not contain valid configuration information. Configure your doppler and save the configuration with the “save” command. This message will be printed at start up time. EEPROM not present The 93C56 chip may not be present. Make sure it is installed and contains saved parameters. EEPROM load aborted, Pressing any button (1-8) at start up time will prevent defaults installed the MicroFinder from loading the saved configuration. Illegal number of antenna The MicroFinder will only support 3, 4, 6, or 8 elements. element antenna systems. *** Input Buffer Overflow You typed more characters than the MicroFinder can accept. Enter shorter commands. Invalid rate The antenna rotation rates are numbered 1-5. Use only 1-5 to specify rotation rates. Pointer not zeroed This message will appear at start up time if the correctly pointer does not reset properly. There may be problems with the motor wiring, the index sensor, or the pointer may be mechanically jammed. Fixing these problems allow the pointer to work correctly.

AHHA! Solutions September 13, 2000 MicroFinder Operator's Guide 33 Version 2.0.2a Process id bad An unknown process id (PID) was specified for a process control command. Use “Appendix B” in the Command Reference Guide to select an available PID. QSD! You entered a command that is unknown to the MicroFinder. Refer to the Command Reference Guide. Unknown EEPROM An incompatible version of the MicroFinder version embedded software, or an external computer program, saved a configuration to the EEPROM that the MicroFinder is unable to use. Reconfigure your doppler then save the configuration. Value is not in range A MicroFinder command required a specific range or value argument. The value you entered is not compatible with that command. See the Command Reference Guide.

AHHA! Solutions September 13, 2000 MicroFinder Operator's Guide 34 Version 2.0.2a Command Reference

AHHA! Solutions September 13, 2000 MicroFinder Operator's Guide 35 Version 2.0.2a Command Introduction

This reference describes each command used by the MicroFinder Doppler. You can use this for information on a specific command. If you need information on how to operate or calibrate the doppler unit, please refer to the “MicroFinder Doppler Operator’s Guide.” Commands are sorted into three sections. · The first section, User Commands, contains commands that are most likely to be used in day-to-day operation of the doppler. · The second section, Advanced Commands, is for commands that may be used to setup or “tune” the doppler for “out of the ordinary” type of operations. · The third section, Debug Commands, may be used when constructing, debugging, or testing the doppler and its hardware. · Warning: Commands in the Advanced or Debug sections are normally not used for “day to day” operation of the doppler. These commands in some cases can cause you to lose your settings and may require a total reset of the MicroFinder system.

Each command is detailed on one page. The conventions used in this manual are as follows. Optional arguments for the command are shown in square brackets. This means you do not have to enter the argument, but if you do enter the argument do not enter the brackets. An example of optional arguments is shown in the rotation command: rotation [1-5] | [?]

When a choice of arguments possible, each alternative argument is shown separated by an “or bar”. The rotation example just used also shows an alternate argument and or-bar. Each command description includes examples of use. All examples of output from the doppler are printed in the Courier Font. Each command must be spelled correctly, and there may be zero or more arguments. When the doppler can not understand your command, you will be informed with a response of “QSD!”. This is the doppler’s way of telling you the attempted command could not be executed. Some commands may be abbreviated. Each command description shows the abbreviation in parenthesis on the right hand side of the description. For instance, the alarm command may be abbreviated to "al" and the description looks like: alarm

AHHA! Solutions September 13, 2000 MicroFinder Operator's Guide 36 Version 2.0.2a User Commands User commands supply the most basic, and commonly used, functionality for MicroFinder configuration.

asw

asw [# 0|1]

asw is the antenna switch configuration command. Use this command when you wish to set or change the number of antenna elements or the logic switching level generated by the CPU. The doppler supports antenna configurations of 3, 4, 6, and 8 element antennas. With no argument, asw will show the current configuration in memory. This may be different from the parameter stored in EEPROM if you have not yet saved your configuration. Examples:

dop >asw Antenna elements : 04 Antenna switch : low

dop >asw 8 1 Antenna elements : 08 Antenna switch : high

AHHA! Solutions September 13, 2000 MicroFinder Operator's Guide 37 Version 2.0.2a baud (ba)

baud [12|24|48|96]

The baud command is used to display or set the baud rate of the serial port. Each argument refers to the baud rates; 1200, 2400, 4800, or 9600. With no arguments this command will show the current baud rate setting. When supplying an argument, the baud rate (if the configuration is save via save) will be used upon reset. This setting is not applied until the MicroFinder is reset. The default baud rate is 4800. This value was selected because most GPS units provide serial data at 4800 baud. The remaining parameters for the serial port are: · 8 data bits · 1 start bit · no parity · no handshake

Examples: dop >baud 48

dop >baud 4800

bearing (be)

bearing

The bearing command will display the current doppler bearing to the transmitter. The bearing information is of the form “%relative/quality%absolute”. Absolute information is only printed when you have configured the MicroFinder for a compass, or you have a GPS unit connected. See the “opt” command for information on configuring your compass. Examples:

dop> bearing %91.8/5%111.6

AHHA! Solutions September 13, 2000 MicroFinder Operator's Guide 38 Version 2.0.2a btab (bt)

btab [B# F#] | [?]

The btab command is used to display or set functions associated with external buttons on doppler. The doppler supports up to 8 buttons. Buttons are numbered 1 through 8, and the functions are specified with a unique four- character code. The button function codes are located in Appendix A of this manual. With no arguments, btab will show the current button configuration. The “?” argument will display a table of the button function codes. Setting a button function is accomplished by supplying button number and function code. Examples: dop >btab 5 bcf1

dop >btab Button #1 : bpoo - Turn the pointer on and off Button #2 : bptr - Switch the stepper motor speed Button #3 : bsnp - Turn snooping on and off … etc…

chkantenna (chk)

chkantenna

The chkantenna command is used to run the antenna check procedure. This is the same test that is performed when the MicroFinder starts. The check procedure measures the voltage on each antenna line and compares the measure value against the others. In order for the test to succeed, the measured voltage must meet the following criteria: · The measured voltage is greater than 0.2 Volts · The measured voltage is less than 4.8 Volts · The measured voltage differs from the previous antenna by less than 0.2 Volts. It is not unusual for antenna measurements to differ by 0.1 volts. The antenna check will indicate an error at the first antenna that violates the above criteria. Note that other antennas may have problems as well. The antenna check routine will only test the number of antennas indicated in the current antenna configuration. If you have saved different configurations with a different number of antennas, you may wish to check each configuration separately. This first example shows the output of the "chkantenna" routine. The antenna switch used for this test uses two diodes (1N914 or 1N4148 type), which results in the 1.6 Volt drop. Dop> chkantenna

AHHA! Solutions September 13, 2000 MicroFinder Operator's Guide 39 Version 2.0.2a Antenna / Volts 1 / 1.6 2 / 1.6 3 / 1.6 4 / 1.6 5 / 1.6 6 / 1.6 7 / 1.6 8 / 1.6

This example shows the result of an error on antenna #5. Because the voltage is too high an error is indicated. In this example an error would also occur if antenna #5 measured zero volts or was outside of the range of 1.4 to 1.8 volts. Dop> chkantenna Antenna / Volts 1 / 1.6 2 / 1.6 3 / 1.6 4 / 1.6 5 / 5.0* 6 / 1.6 7 / 1.6 8 / 1.6 ************************** SWITCH ERROR @ ANTENNA #5 ************************** compass (com)

compass

The compass command will display the current heading, as determined by the magnetic compass. If you do not have a compass configured and attached, this command is not useful. See the “opt” command for more information on configuring your compass. Examples: dop> compass 91.8 help (?)

help [u|a|d|!]

The help command is used to print a summary of the commands to your screen. Using no arguments, the normal user command summaries are printed. Help will display commands associated with “user” (u), “advanced” (a), “debug” (d), or all (!) commands. The help command can also be run by using the “?” command.

AHHA! Solutions September 13, 2000 MicroFinder Operator's Guide 40 Version 2.0.2a mycall (my)

mycall callsign

The mycall command is used to customize your doppler. When entered this way, your callsign will be used as the prompt when a computer is talking to your doppler. The parameter “callsign” should be a string containing your call, with any punctuation you wish. The command will actually take up to 8 characters and can be any printable characters. Example dop> mycall kn6zt -> kn6zt ->

This command is not included in the online help. reset

reset

The reset command performs the same function as if you were to press the reset hardware button. This will restore the doppler to the “power on” state. save

save

The save command is used to save the configuration to the EEPROM. This command writes over the contents of the EEPROM, deleting your old configuration. NOTE: You can not undo this command. Use this command after you have configured the doppler for your set up. Read the section “Configuring Your Doppler” in the User’s Guide. Warning: If you received an EEPROM load error at start up time (see the Operator’s Guide, Error messages), do not save unless you are certain that all of the MicroFinder parameters are what you want.

AHHA! Solutions September 13, 2000 MicroFinder Operator's Guide 41 Version 2.0.2a Advanced Commands These commands are for users wishing to utilize advanced features of the MicroFinder.

Advanced Commands aprs Set or show the APRS parameters alarm Set the alarm conditions calv Start the calibration process config Switch to and set configuration sets execbtn Execute a button function (for host computer use) gps Set the parameters for GPS capturing opt Enable or disable user supplied MicroFinder options ps Display the state MicroFinder software processes qual Show the current bearing quality value rotation Set or show the antenna rotation rate run Resume the operation of a MicroFinder process stop Suspend the operation of a MicroFinder process

alarm (al)

alarm [#]

The alarm command allows you to set, or show, the number of seconds before the "loss of signal" alarm will sound. The alarm is enabled in Filter Mode 2 and if the signal is lost for the entire duration the MicroFinder will sound 3 short beeps. This will continue periodically (ever # seconds) until the signal is restored or the MicroFinder is taken out of Filter Mode 2. Duration is specified in seconds and defaults to 10 seconds. Setting the duration to zero seconds will disable the alarm. Setting durations less than five seconds is not recommended. Example: dop > alarm 10 seconds

dop > alarm 15 15 seconds

AHHA! Solutions September 13, 2000 MicroFinder Operator's Guide 42 Version 2.0.2a aprs

aprs t|f [q [d]]

The aprs command is used to start a process to send periodic bearing and quality information through the serial line. The primary use of this is to provide a data stream compatible with APRS™ . The first argument turns the trace process on or off. Use an argument value of “t” or “1” to start the trace, and “0” or “f” to stop the trace. The second argument is the minimum quality level to be reported. Any quality level, zero to nine is allowable. Quality zero will permit all bearings to be reported. Quality nine will only permit the best quality signals to be reported. The third argument is the number of seconds between bearing reports. Reasonable delay values are one to sixty seconds, depending upon application. Legal values are zero to 3000 seconds (fifty minutes). APRS bearing reporting is implemented in the snoop process (psnp). This function will start the process. You can also turn this on via a button (button function “bapr”).

The format of the output is: %ddd.d/q or %ddd.a/q%aaa.a

In each case, “ddd.d” is the relative bearing, in degrees. The quality of the bearing is represented by “q”. Quality information is on a scale of 0 to 9, 0 is the worst and 9 is the best. If you have configured your system for a compass, the value “aaa.a” is the absolute bearing information in degrees.

Example: dop >aprs 1 5 10 %91.8/5 %111.6/7

See the MicroFinder Construction Guide for information on building the correct cables for computer operation.

AHHA! Solutions September 13, 2000 MicroFinder Operator's Guide 43 Version 2.0.2a calv (ca)

calv [# ##] | -

The calv command is used to set or display the doppler calibration values. With no arguments, calv will display 5 calibration values corresponding to each of the 5 antenna rotation rates. Each calibration value is in the range of 0 to 199. The command “calv -” will place the MicroFinder into “deferred” calibration mode. This mode is used by people who do not have a portable computer to put into their vehicle. Examples: dop> calv 18 32 42 90 173 dop> calv 1 6 dop> calv 6 32 42 90 173

dop> calv -

Hint: Write down the calibration values. If the EEPROM accidentally gets erased, you can reenter them without recalibrating.

config (con)

config [+|-][#]

The config command is the tools you use to manage your configurations. It enables you to determine which configuration set is "active" or "current". A configuration set consists of the antenna configuration (the number of elements and switching level) as well as the radio calibration values. One of the four configurations is marked as "current' which means that the values in that configuration are used by the MicroFinder. "Active" configurations are those that have valid data stored in them and may be used by marking them as "current." When using the config command without arguments, all the configuration sets are shown. Dop> config #1 Antenna 8 H Calibrations 147 147 83 105 105 * #2 Antenna 6 L Calibrations 105 105 95 10 10 #3 Antenna - - Calibrations ------#4 Antenna - - Calibrations ------

Supplying a numeric argument (1 to 4) will mark one of the configuration sets as "current." If the selected configuration set was not active, it will be made active. Dop> config 1 * #1 Antenna 8 H Calibrations 147 147 83 105 105

AHHA! Solutions September 13, 2000 MicroFinder Operator's Guide 44 Version 2.0.2a #2 Antenna 6 L Calibrations 105 105 95 10 10 #3 Antenna - - Calibrations ------#4 Antenna - - Calibrations ------

You may make a configuration active set, without making it current, by preceding the number with a "+". Dop> config +1

You may make a configuration inactive by preceding the number with a "-". Dop> config -1

execbtn (ex)

execbtn XXXX

The execbtn command is used to execute a button function, regardless of the current button table assignments. This allows you (or a computer program) to access all button functions. The argument “XXXX” is a button function code. The function codes are specified in Appendix A of this manual.

Example:

dop >execbtn bswt dop > gps

gps [STRING]

The gps command will show, or allow you to set, the GPS NMEA 2.0 sentence that will be captured. Without an argument the default sentence to be captured is "GPRMC." For most purposes the "GPRMC" sentence is adequate. Should you have a program that requires different sentence you can set it with this command. The MicroFinder is able extract compass information from the "GPRMC" heading and will use that compass information, even if you do not have the MicroFinder compass option. If you set the sentence to something other than "GPRMC" the MicroFinder is not able to extract compass information. In this case the MicroFinder compass option will be used. Example: gps GPXXX

AHHA! Solutions September 13, 2000 MicroFinder Operator's Guide 45 Version 2.0.2a dop> gps gprmc GPRMC

dop> opt

opt [+c | -c | +q | -q]

The opt command is used to set or show the current option configurations. Version 1 of the MicroFinder firmware allows two options: magnetic compass quick look Using arguments “+c” or “+q” will turn on the compass or the quick look options respectively. Arguments “-c” or “-q” will turn off the options. Example:

dop >opt +c +compass -quicklook dop >opt +q +compass +quicklook dop >opt +compass +quicklook ps

ps [t|1||f|0]

The ps command is used to show the process states. Each process in the doppler is either idle (sleeping) or running (awake). This command also lists the state of the driver processes. Supply an argument of “t” or “1” to see a description each process. For more information on the processes in the doppler read the “Doppler Software Architecture” section in the Operator’s Guide. Example:

dop >ps t PROC STATE pbut run User button processor patt sleep Fancy LED display, IMPRESS pdop run Display doppler data on LEDs psnp sleep Send doppler data out serial line pdil run Send doppler data to stepper … etc…

AHHA! Solutions September 13, 2000 MicroFinder Operator's Guide 46 Version 2.0.2a qfilt

qfilt [QQ MISS DEPTH] The qfilt command is used to adjust the operational parameters for the second filter mode (F2). QQ indicates the required signal quality before the sample is to be placed in the queue. Legal values for QQ are zero (0) to nine (9). MISS indicates how many signal samples the MicroFinder may miss before the queue is emptied and the signal is considered lost. Legal values are 1 to the queue DEPTH. DEPTH indicates how many samples must be in the queue before a signal is considered "acquired". Legal values are 1 to 100.

Example: dop> qfilt Queue filter (qual limit/miss limit/min depth) = 4/10/12 dop> qfilt 3 20 12 Queue filter (qual limit/miss limit/min depth) = 3/20/12

qual

The qual command displays the current measurement of the quality of the signal. This value is in the range of 0 to 9. A value of 0 is the worst, and 9 is the best. Quality values correspond to the seven-segment quality display as follows: quality bars segments lit 1 - 3 1 4 - 6 2 7 - 9 3 Example:

dop >qual 7 dop >

AHHA! Solutions September 13, 2000 MicroFinder Operator's Guide 47 Version 2.0.2a rotation (ro)

rotation [1-5|-]

The rotation command will set or show the rotation antenna rate. With no arguments, the current rate will be displayed. With a number argument 1 to 5, the corresponding rate will be set. With the “-” argument, a table showing the rate numbers and their corresponding rate, in Hertz, will be shown. The rates in Hertz are approximate values. Read the section “Configuring Your Doppler” in the Operator’s Guide for more information on Rates. run

run XXXX

The run command will start a process that is currently idle. The process specified by its process ID (XXXX) will start running. Running a currently active process has no effect. See Appendix B for more information on process ID values. Example:

dop >run psnp stop

stop XXXX

The stop command will cause the process specified by the process ID (XXXX) to become idle (sleeping). The process will not wake until you issue a run command or some other function wakes the process. See Appendix B for the process ID codes. Example:

dop >stop psnp

AHHA! Solutions September 13, 2000 MicroFinder Operator's Guide 48 Version 2.0.2a Debug Commands These commands are used when building the MicroFinder, or when debugging problems.

Debug Commands ccw Move the pointer display one step counter clockwise cw Move the pointer display one step clockwise eedump Display the raw contents of the non-volatile store eer Read one location of the non-volatile store eew Write one location of the non-volatile store eezero Erase the non-volatile store ledto Test the 50 LED ring display rb Read a byte from memory (RAM only) rw Read a word from memory (RAM only) seg7 Write a value (0-9,A-F) to the 7 segment display stepto Move the pointer display to a specific location time Show the amount of time the MicroFinder has been running wb Write a byte into memory (RAM only) ww Write a word into memory (RAM only)

ccw

The ccw command is used to move the stepper pointer one step in the counter- clockwise direction. This command is used to test the pointer motor wiring. Use this command only after you have done a stepto command. This sequence of commands will stop the pointer process. To re-enable the pointer, reset the doppler hardware, or wake the pointer process (pdil).

Example:

dop >stepto 62

dop >ccw 62

AHHA! Solutions September 13, 2000 MicroFinder Operator's Guide 49 Version 2.0.2a cw

The cw command is used to move the stepper pointer one step in the clockwise direction. This command is used to test the pointer motor wiring. Use this command only after you have done a stepto command. This sequence of commands will stop the pointer process. To re-enable the pointer, reset the doppler hardware, or wake the pointer process (pdil).

Example:

dop >stepto 62

dop >cw 63

dop >ccw 62 eedump (eed)

eedump

The eedump command will display the raw contents of the EEPROM. Appendix C details the layout of the EEPROM. If you want to change a configuration parameter without using a regular user command you can do so with the eew command. However, this is not a recommended approach for changing configurations.

Example:

Print out the EEPROM to screen dop >eedump 00 - 0003 0340 0603 0501 0000 0204 0000 0000 08 - 0000 0000 0101 0001 0001 0101 0100 0000 10 - 0000 0000 0000 0000 0000 0000 0000 0000 18 - 0000 0000 0000 0000 0000 0000 0000 0000 … etc…

AHHA! Solutions September 13, 2000 MicroFinder Operator's Guide 50 Version 2.0.2a eeread (eer)

eer ##

The eer command will read one EEPROM register at a time. You can get most of the same information from the eedump command. Output from this command is in hexadecimal. Example: dop >eer 01 034f

dop >eer 02 c603

eewrite (eew)

eew AA ####

The eew command will write one EEPROM register at a time. You can use this to patch locations in the EEPROM. Unless you really know what you are doing, beware! This command can really mess with your mind, and your doppler. See Appendix C for the layout of the EEPROM.

Example: dop >eew 01 0340 a7e0

dop >eer 02 0603 12fe

eezero (eez)

eezero

The eezero command is used to clear the EEPROM to an initial, empty state. You will not need to use this command often, if at all. Use this when you believe the data in the EEPROM has become corrupted. The doppler will then reset to “factory defaults” which can then be saved using the eesave command.

AHHA! Solutions September 13, 2000 MicroFinder Operator's Guide 51 Version 2.0.2a ledto (led)

ledto DD

The ledto command is used to light a specific location on the LED ring. It is used when testing the display to determine if an LED is installed incorrectly or is not functioning. The ledto command takes an argument of zero to 199 (doppler degrees) which is translated to the 50 LED display. If the argument is not evenly divisible by 50, two adjacent LEDs will light up. NOTE: Use of this command will stop the LED ring display process ("pled"). This will prevent the doppler from operating normally. When you are finished with this command you should reset the MicroFinder. This command only works when the LED rotation speed is in L1. Set the led rotation speed to L1 with the button "blpt". rbyte (rb)

rb AAAA

The rb allows you to read a single byte from the CPU memory. The address value is anything between 0x0000 and 0xffff. For specific locations in memory, see Appendix D. The argument AAAA and output of this command are in hexadecimal. Example:

dop >rb fd8c 42

rword (rw)

rw AAAA

The rw allows you to read a single word from the CPU memory. The address value is anything between 0x0000 and 0xffff. For specific locations in memory, see Appendix D. The argument AAAA and output of this command are in hexadecimal. Example:

dop >rw fd8c 42ef

AHHA! Solutions September 13, 2000 MicroFinder Operator's Guide 52 Version 2.0.2a seg7

seg7 [#]

The seg7 command is used to place a hex digit value in the seven segment display. Legal values are 0-9 and A-F. The main use for this command is to test the wiring on the seven-segment display, or sometimes for a host computer to display a value. Example:

dop >seg7 4

stepto (st)

stepto ##

The stepto command will cause the connection between the doppler and the stepper pointer to become disconnected. The value specified will become the target for the pointer. You can then use the cw and the ccw commands to move the pointer in one direction or another. These commands are mainly used to debug wiring of the pointer stepper motor. Valid target values are 0 to 199 (“doppler degrees”). WARNING: This command will stop the pointer process, “pdil”. You can restart the process with the “wake” command, or by resetting the doppler. Example:

dop >stepto 62

dop >cw 63 time (ti)

time The time command shows the amount of elapsed time since the last doppler reset or power up. The output is hours, minute, and seconds (hh:mm:ss). The real-time clock in the doppler can record about 32,000 hours. This is almost 4 years elapsed time. We hope this enough! Example: dop >time 48:23:17

AHHA! Solutions September 13, 2000 MicroFinder Operator's Guide 53 Version 2.0.2a wbyte (wb)

wb AAAA ##

The wb command is used to stuff a byte value into a location in memory. This command can be used to patch some runtime parameters or write values to certain output ports. This is normally only used when debugging a newly constructed doppler. The arguments AAAA, ## and output of this command are in hexadecimal. Example:

dop >wb fdfc 42 wword (ww)

ww AAAA ####

The ww command is used to write a word value into memory. This is used to patch some runtime values. Normally this command is only used when debugging a newly constructed doppler. This command writes each byte with a separate CPU instruction. See Appendix D for a list of important locations in memory. The arguments AAAA, #### and output of this command are in hexadecimal. Example:

dop >ww fdfc 1235

AHHA! Solutions September 13, 2000 MicroFinder Operator's Guide 54 Version 2.0.2a Appendix A - Button Function Codes bapr Send bearing to APRS batt Toggle LED attract display bacc Save calibration values bcal Set calibration values bchk Check the antenna switch for proper operation bcfg Change the current configuration to another configuration bcf1 Print 'CB1' to the serial port bcf2 Print 'CB2' to the serial port bcf3 Print 'CB3' to the serial port bcf4 Print 'CB4' to the serial port bcmp Start compass calibrate mode bdim Dim the LED display to 25% of normal bflt Turn on or off quality or quality+qfilt bgps Cause the last captured GPS sentence to be printed to the serial port bhld Pause the LED display blpt Low pass filter the LED display bptr Pointer motor speed bpoo Turn the pointer on and off brat Change antenna rotation rate brng Print the bearing to the serial port bsnp Turn snooping on and off bswt LED display - relative, absolute, compass

AHHA! Solutions September 13, 2000 MicroFinder Operator's Guide 55 Version 2.0.2a Appendix B - Process ID Codes patt “Attract mode”, for fun only. Palm Monitor signal loss, sound alarm pbut Button input pdil Doppler pointer pled Display doppler or compass psnp Send doppler data out serial line danl Analog inputs. dled Manage LED display dcal Calibration driver dcmp Compass calibration driver dser RS-232 input dsnd Play tones for the sounder dsop Print buffered output to the serial port dstp Stepper motor driver

AHHA! Solutions September 13, 2000 MicroFinder Operator's Guide 56 Version 2.0.2a Appendix C - EEPROM Memory Map The memory map of the EEPROM is presented for informational purposes. AHHA! Solutions does not support user modification of the contents of the EEPROM.

Address Description $00 EEPROM Version $01 Antenna rate / Active configuration $02 Button functions #1 & #2 $03 Button functions #3 & #4 $04 Button functions #5 & #6 $05 Button functions #7 & #8 $06 Deferred calibration button functions $07 Compass calibration values $08 Compass calibration values $09 Compass calibration values $0A Compass calibration values $0B Filter parameters $0C Serial port configuration values $0D Option settings $0E Option settings $0F Pointer settings $10 Filter settings $11 Filter settings $12 Filter settings $13 APRS command settings $14 - $18 MyCall string data $19 Alarm settings $1A - $29 Configuration table $2A - $38 Process table

AHHA! Solutions September 13, 2000 MicroFinder Operator's Guide 57 Version 2.0.2a Appendix D - CPU RAM Map

The memory map of selected MicroFinder RAM locations is presented for informational purposes. AHHA! Solutions does not support user modification of the contents of the RAM.

Address Description $F7AC Time since reset, # of hours $F7AE Time since reset, # of minutes $F7AF Time since reset, # of seconds $F7B0 Time since reset, # of millisecond $F7B2 Time since reset, # of microseconds $F7EF Process status "alarm" $F7E9 Process status "analog driver" $F7E8 Process status "APRS snooper" $F7E6 Process status "attract mode" $F7E5 Process status "button input driver" $F7ED Process status "calibration driver" $F7EE Process status "compass calibrator" $F7EA Process status "Pointer" $F7EC Process status "LED driver" $F7E7 Process status "LED ring display" $F7E4 Process status "Serial input" $F7F1 Process status "Serial output" $F7B0 Process status "Sounder driver" $F7EB Process status "Stepper driver" $F85E Captured GPS string (CString)

AHHA! Solutions September 13, 2000 MicroFinder Operator's Guide 58 Version 2.0.2a EPROM 2 Error Messages 33 A execbtn 45 Absolute Display 24 Alarm 7, 12, 29 F APRS 2, 31, 43 Audio Interference 29 Filtering alarm 29 intermittent transmitters 28 B marginal signals 26 baud 38 reflections 27 Bearing 2, 4, 38 warning 29 beeps 32 btab 39 G Button 7 table 7 GPS 2, 30 Buttons 4 H C help 40 Calibration 14 Compass 20 Initial setup 15 L setting up 42, 44, 45 LED calv 42, 44, 45 blinking 29 ccw 49 Circuit Description 5 CLI See Command Processor M Command mycall 41 user 37 Command Introduction 36 Command Processor 10, 13 O Commands 10 Options 46 advanced 42 display 26 debug 49 help 40 Compass 2, 26, 40 P Calibration 20 Configuration 18 Parameters 12 antenna 37 Pointer 4 physical 13 Processes 6 saving 41 ps 46 showing 20 cw50 Q qfilt 47 D qual 47 Direction Finding Calibration 17 Display 4 R options 26 Doppler Operation 23 rb 52 Reset 41 Switch 4 E Reset Switch 4 eedump 50 rotation 48 EEPROM 2 RS 232 5 eew 51 run48 eezero 51 rw 52

AHHA! Solutions September 13, 2000 MicroFinder Operator's Guide 59 Version 2.0.2a S button 39 time 53 save 41 Transmit seg7 53 disable 31 Serial Trouble shooting 31 baud rate 38 squelch 28 stepto 53 W stop 48 wb54 ww T Table

AHHA! Solutions September 13, 2000 MicroFinder Operator's Guide 60 Version 2.0.2a Suggestions

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AHHA! Solutions September 13, 2000 MicroFinder Operator's Guide 61 Version 2.0.2a