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Ignore whitespace Rev 2188 → Rev 2189

/branches/dongfang_FC_rewrite/timer2.c
1,36 → 1,18
#include <avr/io.h>
#include <avr/interrupt.h>
#include "eeprom.h"
#include "rc.h"
#include "attitude.h"
#include "timer2.h"
 
#define COARSERESOLUTION 1
 
#ifdef COARSERESOLUTION
#define NEUTRAL_PULSELENGTH 938
#define STABILIZATION_LOG_DIVIDER 6
#define SERVOLIMIT 500
#define SCALE_FACTOR 4
#if (SERVO_RESOLUTION == COARSE)
#define CS2 ((1<<CS21)|(1<<CS20))
 
#else
 
#define NEUTRAL_PULSELENGTH 3750
#define STABILIZATION_LOG_DIVIDER 4
#define SERVOLIMIT 2000
#define SCALE_FACTOR 16
#define CS2 (1<<CS21)
#endif
 
#define MAX_SERVOS 8
#define FRAMELEN ((NEUTRAL_PULSELENGTH + SERVOLIMIT) * staticParams.servoCount + 128)
#define MIN_PULSELENGTH (NEUTRAL_PULSELENGTH - SERVOLIMIT)
#define MAX_PULSELENGTH (NEUTRAL_PULSELENGTH + SERVOLIMIT)
#define FRAMELEN (PULSELENGTH_2200 * staticParams.servoCount + 128)
 
//volatile uint8_t servoActive = 0;
volatile uint8_t recalculateServoTimes = 0;
volatile uint16_t servoValues[MAX_SERVOS];
volatile uint16_t previousManualValues[2];
// volatile uint8_t servoActive = 0;
// volatile uint8_t recalculateServoTimes = 0;
volatile uint16_t pwmChannels[MAX_PWMCHANNELS];
 
#define HEF4017R_ON PORTC |= (1<<PORTC6)
#define HEF4017R_OFF PORTC &= ~(1<<PORTC6)
78,9 → 60,6
TIMSK2 &= ~((1 << OCIE2B) | (1 << TOIE2));
TIMSK2 |= (1 << OCIE2A);
 
for (uint8_t axis=0; axis<2; axis++)
previousManualValues[axis] = dynamicParams.servoManualControl[axis] * SCALE_FACTOR;
 
SREG = sreg;
}
 
97,52 → 76,8
/*****************************************************
* Control Servo Position
*****************************************************/
int16_t calculateStabilizedServoAxis(uint8_t axis) {
int32_t value = attitude[axis] >> STABILIZATION_LOG_DIVIDER; // between -500000 to 500000 extreme limits. Just about
// With full blast on stabilization gain (255) we want to convert a delta of, say, 125000 to 2000.
// That is a divisor of about 1<<14. Same conclusion as H&I.
value *= staticParams.servoConfigurations[axis].stabilizationFactor;
value = value >> 8;
if (staticParams.servoConfigurations[axis].flags & SERVO_STABILIZATION_REVERSE)
return -value;
return value;
}
 
// With constant-speed limitation.
uint16_t calculateManualServoAxis(uint8_t axis, uint16_t manualValue) {
int16_t diff = manualValue - previousManualValues[axis];
uint8_t maxSpeed = staticParams.servoManualMaxSpeed;
if (diff > maxSpeed) diff = maxSpeed;
else if (diff < -maxSpeed) diff = -maxSpeed;
manualValue = previousManualValues[axis] + diff;
previousManualValues[axis] = manualValue;
return manualValue;
}
 
// add stabilization and manual, apply soft position limits.
// All in a [0..255*SCALE_FACTOR] space (despite signed types used internally)
int16_t featuredServoValue(uint8_t axis) {
int16_t value = calculateManualServoAxis(axis, dynamicParams.servoManualControl[axis] * SCALE_FACTOR);
value += calculateStabilizedServoAxis(axis);
int16_t limit = staticParams.servoConfigurations[axis].minValue * SCALE_FACTOR;
if (value < limit) value = limit;
limit = staticParams.servoConfigurations[axis].maxValue * SCALE_FACTOR;
if (value > limit) value = limit;
return value;
}
 
uint16_t servoValue(uint8_t axis) {
int16_t value;
if (axis<2) value = featuredServoValue(axis);
else value = 128 * SCALE_FACTOR; // dummy. Replace by something useful for servos 3..8.
// Shift out of the [0..255*SCALE_FACTOR] space
value -= (128 * SCALE_FACTOR);
if (value < -SERVOLIMIT) value = -SERVOLIMIT;
else if (value > SERVOLIMIT) value = SERVOLIMIT;
// Shift into the [NEUTRAL_PULSELENGTH-SERVOLIMIT..NEUTRAL_PULSELENGTH+SERVOLIMIT] space.
return value + NEUTRAL_PULSELENGTH;
}
 
/*
void calculateServoValues(void) {
if (!recalculateServoTimes) return;
for (uint8_t axis=0; axis<MAX_SERVOS; axis++) {
150,9 → 85,8
}
recalculateServoTimes = 0;
}
*/
 
uint8_t servoMap[] = {2,3,0,1,4,5,6,7};
 
ISR(TIMER2_COMPA_vect) {
static uint16_t remainingPulseTime;
static uint8_t servoIndex = 0;
162,17 → 96,16
// Pulse is over, and the next pulse has already just started. Calculate length of next pulse.
if (servoIndex < staticParams.servoCount) {
// There are more signals to output.
sumOfPulseTimes += (remainingPulseTime = servoValues[servoMap[servoIndex]]);
sumOfPulseTimes += (remainingPulseTime = pwmChannels[servoIndex]); //pwmChannels[servoMap[servoIndex]]);
servoIndex++;
} else {
// There are no more signals. Reset the counter and make this pulse cover the missing frame time.
remainingPulseTime = FRAMELEN - sumOfPulseTimes;
sumOfPulseTimes = servoIndex = 0;
recalculateServoTimes = 1;
HEF4017R_ON;
}
}
 
// Schedule the next OCR2A event. The counter is already reset at this time.
if (remainingPulseTime > 256+128) {
// Set output to reset to zero at next OCR match. It does not really matter when the output is set low again,
179,18 → 112,18
// as long as it happens once per pulse. This will, because all pulses are > 255+128 long.
OCR2A = 255;
TCCR2A &= ~(1<<COM2A0);
remainingPulseTime-=256;
remainingPulseTime -= 256;
} else if (remainingPulseTime > 256) {
// Remaining pulse lengths in the range [256..256+128] might cause trouble if handled the standard
// way, which is in chunks of 256. The remainder would be very small, possibly causing an interrupt on interrupt
// condition. Instead we now make a chunk of 128. The remaining chunk will then be in [128..255] which is OK.
remainingPulseTime-=128;
OCR2A=127;
remainingPulseTime -= 128;
} else {
// Set output to high at next OCR match. This is when the 4017 counter will advance by one. Also set reset low
TCCR2A |= (1<<COM2A0);
OCR2A = remainingPulseTime-1;
remainingPulseTime=0;
remainingPulseTime = 0;
HEF4017R_OFF; // implement servo-disable here, by only removing the reset signal if ServoEnabled!=0.
}
}