197607 Byte Magazine Vol 00-11 Core Memories.Pdf
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SUPPLIES THE MISSING LINK AC·3D CASSETTE INTERFACE Been looking for a practical way to input for two aud io cassette recorders (not in and dump programs to your computer? cluded in the kit). One recorder's tape may Well your search is over. be read while the second is recording a new updated tape; making it possibleto generate With our new AC-30 Cassette I nterface you new program tapes, data tapes and to create wi II be able to store and input program program object tapes while reading and data to any computer system having RS- assembling program source tapes. The oper 232 serial interfaces and a UART circuit ating mode for each recorder is selected by having an accessible 16X clock frequency. switches on the front panel and LED indi Data format is the "Kansas City" standard cators show the mode that is selected at which was selected for its tolerance of any particular time. Computer controlled speed variations in the recording device. record, play and motor control commands The AC-30 may be used with any cassette may be used with this system if they are recorder of reasonable quality. available from the terminal being used. This If both your computer and terminal have feature is available on our CT-1 024 terminal accessible 16X UART clocks and will oper if the CT-CA cursor control card is installed. ate at 300 baud-as do our 6800 computer The AC-30 is housed in a 12%" x 3" x 12%" and CT-1024 terminal system-the AC-30 aluminum chassis. It is powered by a self may be used between the terminal's serial contained 115/230 Volt AC 50-60 Hz interface and the computers control inter power supply. Data is FSK format using face. This eliminates the need for a separate 1200 Hz and 2400 Hz at a 300 baud data interface to drive the cassette unit. It also rate. Recorder speed tolerance need be allows you to use the computer system's only ± 20%. tape load and dump routines built into Mikbug® or similar ROM software. ®Trademark Motorola Independent control circuits are provided AC-30 Cassette Interface Kit $79.50 ppd Southwest Technical Products Corporation 219 W. Rhapsody San Antonio, Texas 78216 How to use your computer with analog signals ANALOG ANALOG INPUTS -2.56 V SAMPLE OUTPUTS TO COMPUTER COMPUTER & - 2. 56 V +2.56 V INPUT INPUT OUTPU T HOLD TO BUFFE RS PORTS PORTS CIRCUITS + 2. 56 V JOYSTICKS ascI LLQSCQPES PRESSURE TRANSOUCERS RECORDERS GAMES DATA T ER MIN ALS MODEMS METERS PROCESS CONTROL DEVICES en en FANS :::J ::J AMP LIFI ERS ro ro PR INT ERS TEMPERAT URE D EV ICES MOT OR S L IGHT SEN SOR S ~ «~ « PLOTTERS INST RUMENTS o o VISU AL MON ITORS GAUGES a: a: w CONTRO L DEV ICES SCALES w f I NST RUME NTS f HYDRAU L IC SYSTE MS ::J :::J 0.. HEATERS SECURI T Y DEVICES 0.. :2 :2 MODEMS MAGNETIC TAPES o o u RECEIVERS FREOUENCY SENSORS u VA L VES :2 PRODUCTION LINE D EVICES o ALARMS f- o INERTIAL DEVICES a: RO BOTS u. FI LTERS DI GITAL F~~~~~~~~ ~~~~~ l OUTPUT Now you have a way to get analog The D+ 7 A lets you input and output of Cromemco's design leadership. The information into and out of your micro analog data with all sorts of devices: D+ 7 A and all Cromemco peripherals computer. It's an easy, fast, and unbe joysticks, ham radio gear, measurement are of advanced computer-grade quality. lievably inexpensive way. instruments, machine tools, transducers, The D+7 A is solder-masked and printed It's Cromemco's new D+7AT M high control systems, motors, recorders, and with full legend for easy, error-free performance I/O module which gives plotters, to name just a few. assembly. you: NO FURTHER SOFTWARE NEEDED • 7 channels of 8-bit analog-to-digital The D+ 7 A I/O plugs directly into the conversion (to input analog data to AT COMPUTER STORES/MAIL the computer) Altair 8800 or IMSAI 8080 microcom • 7 channels of digital-to-analog con puters. Analog signal range is from -2.56 You can get the D+7A at computer version (to output computer data to +i56 volts (20-millivolt increments) stores in either kit or assembled form. in analog form) on both input and output sides. Or order directly by mail from Cro • an 8-bit parallel I/O port to input Simple "Input" and "Output" in memco. Delivery is from stock to 30 and output data in digital form. structions initiate A/D conversion and days. The D+7 A is certain to be popular • a fast conversion time of 5 micro read in or out the ensuing 8 bits of data. so order now .. No further software is required. During seconds. 0+7ATMI/okit ....... .. .. $145 conversion the D+ 7 A holds down the 0+7 ATM I/O assembled ........... $245 computer "Ready" line. A MULTITUDE OF USES Addresses of the input and output Each 0+7 A includes a connector to con- The D+7A makes it easy to use your ports a re jumper-wire selectable in nect to the 8 input and 8 output ports. computer for the jobs you want it to blocks of 8. Sample-and-hold circuitry Shipped prepaid if fully paid with order. do-such as process control, digital is used to "latch" the analog outputs. California users add 6% sales tax. filtering, games, oscilloscope graphics, Mastercharge and BankAmericard accepted LOW-PRICED speech recognition, speech and music with signed order. Please include card synthesis. The low price of the D+7A is a result number and expiration date. Cromemeo Specialists in computer peripherals One First SI., Los Altos, CA 94022 • (415) 941-2967 We commissioned Robert Tinney to do an oil painting for the Bicentennial cover of BYTE. The theme is a humorous anachronism in several re spects. The obvious anachronism is the 18th century philosopher and patriot sitting at a very 20th century hard copy terminal, holding a reference volume, America's first best seller. It is not clear how the quill pen and ink output mechanism of the hard copy terminal works. There are more anachronisms in the picture, which we'll leave to BYTE readers to point out. A full-size poster of the original painting in color is available from BYTE (see page 96). page 6 page 58 Robert Suding asks "Why Wait?" in a rhetorical fashion, and proceeds to demonstrate his schematic of a fast cassette interface which uses software In This ~~TI and a one bit 10 port to implement an audio cassette system. Have you ever looked through the Machine Language Programming for What's it Ii ke to be isolated from sur p Ius catalogs and wondered the "8008" and Similar Microcompu bountiful US surplus markets? In a whether those memory core planes ters, a manual which is sold by Scelbi sense, it means a relative isolation and stacks advertised could be used for Computer Consulting Inc. In this issue from modern LSI products, as Dr anything other than tea strainers? For is the first of three direct reprints from Michael N Hayes reports on his theory and practical information on that manual: Chapter 1 which de experiences in Tokyo and Manila in Coincident Current Ferrite Core scribes the 8008 instruction set. December 1975. Read his report on Memories turn to James R Jones' Surplus Electronics in Tokyo and article. One of the problems of in terfaci ng Manila in this issue. unknown electronics is figuring out Bruce A Anderson describ es his how to accomplish the match. Ken There are many ways to wire a experiences Assembling a Sphere in hi s Barbier built a character generator, circuit. The most common manufac rev iew of what rolled out of the went out and bought a TV set, then turing method is printed wiring. But production facilities in Bountifu l UT faced the problem of building a driver you can also Make Your Own Printed last fal l. for the TV. Th e result was The Circuits at home, using techniques "I gnorance is Bliss" Television Drive described by James Hogenson in his One of the most important ques Circuit. article. tions people ask is "how do I learn about what a computer does? " One While not really promising the en One of the most interestin g app lic a way to help out friends who are trying tire big blue sky, when you Put the tions of computers is in the area of to get into the swing of things with "Do Everything" Chip in your Next grap hic outputs. Using a vector CRT programming is to implement a version Design you'll end up with a computer or a plotter, dr awi ng pictures of of Charles Howerton's Educator-8080 that has five separate programmable mathematically ge nerated abstractions program so that they can interactively real time clocks, standard serial com or simple cartoons can be the Explore an 8080 with Educator-8080. munications data rates from 110 baud beginning of hours of fun. Bu t A Plot to 9600 baud, automatic generation of Is Incomplete Without Characters so A thorough explanation of the an 8080's RST n interrupt vectors, an Richard J Lerseth concocted some instruction set should accompany any 8 bit parallel output and an 8 bit software descri bed in hi s article on the product intended for wide distribu parallel input port.