ardupilot/libraries/APM_RC/APM_RC_APM2.cpp

278 lines
8.3 KiB
C++

/*
APM_RC_APM2.cpp - Radio Control Library for Ardupilot Mega 2.0. Arduino
Code by Jordi Muñoz and Jose Julio. DIYDrones.com
This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
RC Input : PPM signal on IC4 pin
RC Output : 11 Servo outputs (standard 20ms frame)
Methods:
Init() : Initialization of interrupts an Timers
OutpuCh(ch,pwm) : Output value to servos (range : 900-2100us) ch=0..10
InputCh(ch) : Read a channel input value. ch=0..7
GetState() : Returns the state of the input. 1 => New radio frame to process
Automatically resets when we call InputCh to read channels
*/
#include "APM_RC_APM2.h"
#if defined(ARDUINO) && ARDUINO >= 100
#include "Arduino.h"
#else
#include "WProgram.h"
#endif
#if !defined(__AVR_ATmega1280__) && !defined(__AVR_ATmega2560__)
# error Please check the Tools/Board menu to ensure you have selected Arduino Mega as your target.
#else
// Variable definition for Input Capture interrupt
volatile uint16_t APM_RC_APM2::_PWM_RAW[NUM_CHANNELS] = {2400,2400,2400,2400,2400,2400,2400,2400};
volatile uint8_t APM_RC_APM2::_radio_status=0;
/****************************************************
Input Capture Interrupt ICP5 => PPM signal read
****************************************************/
void APM_RC_APM2::_timer5_capt_cb(void)
{
static uint16_t prev_icr;
static uint8_t frame_idx;
uint16_t icr;
uint16_t pwidth;
icr = ICR5;
// Calculate pulse width assuming timer overflow TOP = 40000
if ( icr < prev_icr ) {
pwidth = ( icr + 40000 ) - prev_icr;
} else {
pwidth = icr - prev_icr;
}
// Was it a sync pulse? If so, reset frame.
if ( pwidth > 8000 ) {
frame_idx=0;
} else {
// Save pulse into _PWM_RAW array.
if ( frame_idx < NUM_CHANNELS ) {
_PWM_RAW[ frame_idx++ ] = pwidth;
// If this is the last pulse in a frame, set _radio_status.
if (frame_idx >= NUM_CHANNELS) {
_radio_status = 1;
}
}
}
// Save icr for next call.
prev_icr = icr;
}
// Constructors ////////////////////////////////////////////////////////////////
APM_RC_APM2::APM_RC_APM2()
{
}
// Public Methods //////////////////////////////////////////////////////////////
void APM_RC_APM2::Init( Arduino_Mega_ISR_Registry * isr_reg )
{
// --------------------- TIMER1: OUT1 and OUT2 -----------------------
pinMode(12,OUTPUT); // OUT1 (PB6/OC1B)
pinMode(11,OUTPUT); // OUT2 (PB5/OC1A)
// WGM: 1 1 1 0. Clear Timer on Compare, TOP is ICR1.
// CS11: prescale by 8 => 0.5us tick
TCCR1A =((1<<WGM11));
TCCR1B = (1<<WGM13)|(1<<WGM12)|(1<<CS11);
ICR1 = 40000; // 0.5us tick => 50hz freq
OCR1A = 0xFFFF; // Init OCR registers to nil output signal
OCR1B = 0xFFFF;
// --------------- TIMER4: OUT3, OUT4, and OUT5 ---------------------
pinMode(8,OUTPUT); // OUT3 (PH5/OC4C)
pinMode(7,OUTPUT); // OUT4 (PH4/OC4B)
pinMode(6,OUTPUT); // OUT5 (PH3/OC4A)
// WGM: 1 1 1 0. Clear Timer on Compare, TOP is ICR4.
// CS41: prescale by 8 => 0.5us tick
TCCR4A =((1<<WGM41));
TCCR4B = (1<<WGM43)|(1<<WGM42)|(1<<CS41);
OCR4A = 0xFFFF; // Init OCR registers to nil output signal
OCR4B = 0xFFFF;
OCR4C = 0xFFFF;
ICR4 = 40000; // 0.5us tick => 50hz freq
//--------------- TIMER3: OUT6, OUT7, and OUT8 ----------------------
pinMode(3,OUTPUT); // OUT6 (PE5/OC3C)
pinMode(2,OUTPUT); // OUT7 (PE4/OC3B)
pinMode(5,OUTPUT); // OUT8 (PE3/OC3A)
// WGM: 1 1 1 0. Clear timer on Compare, TOP is ICR3
// CS31: prescale by 8 => 0.5us tick
TCCR3A =((1<<WGM31));
TCCR3B = (1<<WGM33)|(1<<WGM32)|(1<<CS31);
OCR3A = 0xFFFF; // Init OCR registers to nil output signal
OCR3B = 0xFFFF;
OCR3C = 0xFFFF;
ICR3 = 40000; // 0.5us tick => 50hz freq
//--------------- TIMER5: PPM INPUT ---------------------------------
// Init PPM input on Timer 5
pinMode(48, INPUT); // PPM Input (PL1/ICP5)
pinMode(45, OUTPUT); // OUT10 (PL4/OC5B)
pinMode(44, OUTPUT); // OUT11 (PL5/OC5C)
// WGM: 1 1 1 1. Fast PWM, TOP is OCR5A
// COM all disabled.
// CS51: prescale by 8 => 0.5us tick
// ICES5: Input Capture on rising edge
TCCR5A =((1<<WGM50)|(1<<WGM51));
// Input Capture rising edge
TCCR5B = ((1<<WGM53)|(1<<WGM52)|(1<<CS51)|(1<<ICES5));
OCR5A = 40000; // 0.5us tick => 50hz freq. The input capture routine
// assumes this 40000 for TOP.
isr_reg->register_signal( ISR_REGISTRY_TIMER5_CAPT, _timer5_capt_cb );
// Enable Input Capture interrupt
TIMSK5 |= (1<<ICIE5);
}
void APM_RC_APM2::OutputCh(unsigned char ch, uint16_t pwm)
{
pwm=constrain(pwm,MIN_PULSEWIDTH,MAX_PULSEWIDTH);
pwm<<=1; // pwm*2;
switch(ch)
{
case 0: OCR1B=pwm; break; // out1
case 1: OCR1A=pwm; break; // out2
case 2: OCR4C=pwm; break; // out3
case 3: OCR4B=pwm; break; // out4
case 4: OCR4A=pwm; break; // out5
case 5: OCR3C=pwm; break; // out6
case 6: OCR3B=pwm; break; // out7
case 7: OCR3A=pwm; break; // out8
case 9: OCR5B=pwm; break; // out10
case 10: OCR5C=pwm; break; // out11
}
}
void APM_RC_APM2::enable_out(uint8_t ch)
{
switch(ch) {
case 0: TCCR1A |= (1<<COM1B1); break; // CH_1 : OC1B
case 1: TCCR1A |= (1<<COM1A1); break; // CH_2 : OC1A
case 2: TCCR4A |= (1<<COM4C1); break; // CH_3 : OC4C
case 3: TCCR4A |= (1<<COM4B1); break; // CH_4 : OC4B
case 4: TCCR4A |= (1<<COM4A1); break; // CH_5 : OC4A
case 5: TCCR3A |= (1<<COM3C1); break; // CH_6 : OC3C
case 6: TCCR3A |= (1<<COM3B1); break; // CH_7 : OC3B
case 7: TCCR3A |= (1<<COM3A1); break; // CH_8 : OC3A
case 9: TCCR5A |= (1<<COM5B1); break; // CH_10 : OC5B
case 10: TCCR5A |= (1<<COM5C1); break; // CH_11 : OC5C
}
}
void APM_RC_APM2::disable_out(uint8_t ch)
{
switch(ch) {
case 0: TCCR1A &= ~(1<<COM1B1); break; // CH_1 : OC1B
case 1: TCCR1A &= ~(1<<COM1A1); break; // CH_2 : OC1A
case 2: TCCR4A &= ~(1<<COM4C1); break; // CH_3 : OC4C
case 3: TCCR4A &= ~(1<<COM4B1); break; // CH_4 : OC4B
case 4: TCCR4A &= ~(1<<COM4A1); break; // CH_5 : OC4A
case 5: TCCR3A &= ~(1<<COM3C1); break; // CH_6 : OC3C
case 6: TCCR3A &= ~(1<<COM3B1); break; // CH_7 : OC3B
case 7: TCCR3A &= ~(1<<COM3A1); break; // CH_8 : OC3A
case 9: TCCR5A &= ~(1<<COM5B1); break; // CH_10 : OC5B
case 10: TCCR5A &= ~(1<<COM5C1); break; // CH_11 : OC5C
}
}
uint16_t APM_RC_APM2::InputCh(unsigned char ch)
{
uint16_t result;
uint16_t result2;
if (_HIL_override[ch] != 0) {
return _HIL_override[ch];
}
// Because servo pulse variables are 16 bits and the interrupts are running values could be corrupted.
// We dont want to stop interrupts to read radio channels so we have to do two readings to be sure that the value is correct...
result = _PWM_RAW[ch]>>1; // Because timer runs at 0.5us we need to do value/2
result2 = _PWM_RAW[ch]>>1;
if (result != result2)
result = _PWM_RAW[ch]>>1; // if the results are different we make a third reading (this should be fine)
// Limit values to a valid range
result = constrain(result,MIN_PULSEWIDTH,MAX_PULSEWIDTH);
_radio_status=0; // Radio channel read
return(result);
}
unsigned char APM_RC_APM2::GetState(void)
{
return(_radio_status);
}
// InstantPWM is not implemented!
void APM_RC_APM2::Force_Out(void) { }
void APM_RC_APM2::Force_Out0_Out1(void) { }
void APM_RC_APM2::Force_Out2_Out3(void) { }
void APM_RC_APM2::Force_Out6_Out7(void) { }
/* ---------------- OUTPUT SPEED CONTROL ------------------ */
void APM_RC_APM2::SetFastOutputChannels(uint32_t chmask, uint16_t speed_hz)
{
uint16_t icr = _map_speed(speed_hz);
if ((chmask & ( _BV(CH_1) | _BV(CH_2))) != 0) {
ICR1 = icr;
}
if ((chmask & ( _BV(CH_3) | _BV(CH_4) | _BV(CH_5))) != 0) {
ICR4 = icr;
}
if ((chmask & ( _BV(CH_6) | _BV(CH_7) | _BV(CH_8))) != 0) {
ICR3 = icr;
}
}
// allow HIL override of RC values
// A value of -1 means no change
// A value of 0 means no override, use the real RC values
bool APM_RC_APM2::setHIL(int16_t v[NUM_CHANNELS])
{
uint8_t sum = 0;
for (unsigned char i=0; i<NUM_CHANNELS; i++) {
if (v[i] != -1) {
_HIL_override[i] = v[i];
}
if (_HIL_override[i] != 0) {
sum++;
}
}
if (sum == 0) {
return 0;
} else {
return 1;
}
_radio_status = 1;
}
void APM_RC_APM2::clearOverride(void)
{
for (unsigned char i=0; i<NUM_CHANNELS; i++) {
_HIL_override[i] = 0;
}
}
#endif