HAL Manual V2.5, 2018-10-21 I

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HAL Manual V2.5, 2018-10-21 I HAL Manual V2.5, 2018-10-21 i HAL Manual V2.5, 2018-10-21 HAL Manual V2.5, 2018-10-21 ii Contents I Hardware Abstract Layer1 1 HAL Introduction 2 1.1 HAL is based on traditional system design techniques................................2 1.1.1 Part Selection.................................................2 1.1.2 Interconnection Design............................................2 1.1.3 Implementation................................................3 1.1.4 Testing....................................................3 1.1.5 Summary...................................................3 1.2 HAL Concepts....................................................4 1.3 HAL components...................................................5 1.3.1 External Programs with HAL hooks.....................................5 1.3.2 Internal Components.............................................5 1.3.3 Hardware Drivers...............................................6 1.3.4 Tools and Utilities..............................................6 1.4 Timing Issues In HAL................................................6 2 Advanced HAL Tutorial 8 2.1 Introduction......................................................8 2.1.1 Notation...................................................8 2.1.2 Tab-completion................................................8 2.1.3 The RTAPI environment...........................................8 2.2 A Simple Example..................................................9 2.2.1 Loading a component.............................................9 2.2.2 Examining the HAL.............................................9 2.2.3 Making realtime code run.......................................... 10 2.2.4 Changing Parameters............................................. 12 2.2.5 Saving the HAL configuration........................................ 12 2.2.6 Exiting halrun................................................ 13 2.2.7 Restoring the HAL configuration....................................... 13 HAL Manual V2.5, 2018-10-21 iii 2.2.8 Removing HAL from memory........................................ 13 2.3 Halmeter....................................................... 13 2.4 Stepgen Example................................................... 15 2.4.1 Installing the components.......................................... 15 2.4.2 Connecting pins with signals......................................... 16 2.4.3 Setting up realtime execution - threads and functions............................ 17 2.4.4 Setting parameters.............................................. 18 2.4.5 Run it!.................................................... 19 2.5 Halscope....................................................... 19 2.5.1 Hooking up the scope probes......................................... 21 2.5.2 Capturing our first waveforms........................................ 24 2.5.3 Vertical Adjustments............................................. 25 2.5.4 Triggering................................................... 26 2.5.5 Horizontal Adjustments........................................... 28 2.5.6 More Channels................................................ 29 2.5.7 More samples................................................. 30 3 General Reference 31 3.1 General Naming Conventions............................................. 31 3.2 Hardware Driver Naming Conventions....................................... 31 3.2.1 Pin/Parameter names............................................. 31 3.2.2 Function Names............................................... 32 4 Canonical Device Interfaces 34 4.1 Introduction...................................................... 34 4.2 Digital Input...................................................... 34 4.2.1 Pins...................................................... 34 4.2.2 Parameters.................................................. 34 4.2.3 Functions................................................... 34 4.3 Digital Output..................................................... 34 4.3.1 Pins...................................................... 35 4.3.2 Parameters.................................................. 35 4.3.3 Functions................................................... 35 4.4 Analog Input..................................................... 35 4.4.1 Pins...................................................... 35 4.4.2 Parameters.................................................. 35 4.4.3 Functions................................................... 35 4.5 Analog Output.................................................... 35 4.5.1 Pins...................................................... 35 4.5.2 Parameters.................................................. 36 4.5.3 Functions................................................... 36 HAL Manual V2.5, 2018-10-21 iv 5 HAL Tools 37 5.1 Halcmd........................................................ 37 5.2 Halmeter....................................................... 37 5.3 Halscope....................................................... 38 6 Basic HAL Tutorial 39 6.1 HAL Commands................................................... 39 6.1.1 loadrt..................................................... 40 6.1.2 addf..................................................... 40 6.1.3 loadusr.................................................... 41 6.1.4 net...................................................... 41 6.1.5 setp...................................................... 42 6.1.6 sets...................................................... 43 6.1.7 unlinkp.................................................... 43 6.1.8 Obsolete Commands............................................. 43 6.1.8.1 linksp............................................... 43 6.1.8.2 linkps............................................... 44 6.1.8.3 newsig............................................... 44 6.2 HAL Data....................................................... 44 6.2.1 Bit...................................................... 44 6.2.2 Float..................................................... 44 6.2.3 s32...................................................... 44 6.2.4 u32...................................................... 44 6.3 HAL Files....................................................... 45 6.4 HAL Components................................................... 45 6.5 Logic Components.................................................. 45 6.5.1 and2...................................................... 45 6.5.2 not...................................................... 46 6.5.3 or2...................................................... 46 6.5.4 xor2...................................................... 46 6.5.5 Logic Examples............................................... 47 6.6 Conversion Components............................................... 47 6.6.1 weighted_sum................................................ 47 7 Halshow 49 7.1 Starting Halshow................................................... 49 7.2 HAL Tree Area.................................................... 49 7.3 HAL Show Area................................................... 51 7.4 HAL Watch Area................................................... 54 HAL Manual V2.5, 2018-10-21 v 8 HAL Components 56 8.1 Commands and Userspace Components....................................... 56 8.2 Realtime Components List.............................................. 57 8.2.1 Core LinuxCNC components......................................... 57 8.2.2 Logic and bitwise components........................................ 57 8.2.3 Arithmetic and float-components....................................... 58 8.2.4 Type conversion............................................... 59 8.2.5 Hardware drivers............................................... 60 8.2.6 Kinematics.................................................. 60 8.2.7 Motor control................................................. 61 8.2.8 BLDC and 3-phase motor control...................................... 61 8.2.9 Other..................................................... 62 8.3 HAL API calls.................................................... 63 8.4 RTAPI calls...................................................... 64 9 HAL Component Descriptions 66 9.1 Stepgen........................................................ 66 9.2 PWMgen....................................................... 73 9.3 Encoder........................................................ 74 9.4 PID.......................................................... 77 9.5 Simulated Encoder.................................................. 79 9.6 Debounce....................................................... 80 9.7 Siggen......................................................... 80 9.8 lut5.......................................................... 81 10 Parallel Port Driver 83 10.1 Parport......................................................... 83 10.1.1 Installing................................................... 83 10.1.2 Pins...................................................... 84 10.1.3 Parameters.................................................. 85 10.1.4 Functions................................................... 85 10.1.5 Common problems.............................................. 85 10.1.6 Using DoubleStep.............................................. 86 10.2 probe_parport..................................................... 86 10.2.1 Installing................................................... 86 11 HAL Examples 87 11.1 Manual Toolchange.................................................
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