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// ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
// + Copyright (c) 04.2007 Holger Buss
// + Nur für den privaten Gebrauch
// + www.MikroKopter.com
// ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
// + Es gilt für das gesamte Projekt (Hardware, Software, Binärfiles, Sourcecode und Dokumentation),
// + dass eine Nutzung (auch auszugsweise) nur für den privaten (nicht-kommerziellen) Gebrauch zulässig ist.
// + Sollten direkte oder indirekte kommerzielle Absichten verfolgt werden, ist mit uns (info@mikrokopter.de) Kontakt
// + bzgl. der Nutzungsbedingungen aufzunehmen.
// + Eine kommerzielle Nutzung ist z.B.Verkauf von MikroKoptern, Bestückung und Verkauf von Platinen oder Bausätzen,
// + Verkauf von Luftbildaufnahmen, usw.
// ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
// + Werden Teile des Quellcodes (mit oder ohne Modifikation) weiterverwendet oder veröffentlicht,
// + unterliegen sie auch diesen Nutzungsbedingungen und diese Nutzungsbedingungen incl. Copyright müssen dann beiliegen
// ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
// + Sollte die Software (auch auszugesweise) oder sonstige Informationen des MikroKopter-Projekts
// + auf anderen Webseiten oder sonstigen Medien veröffentlicht werden, muss unsere Webseite "http://www.mikrokopter.de"
// + eindeutig als Ursprung verlinkt werden
// ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
// + Keine Gewähr auf Fehlerfreiheit, Vollständigkeit oder Funktion
// + Benutzung auf eigene Gefahr
// + Wir übernehmen keinerlei Haftung für direkte oder indirekte Personen- oder Sachschäden
// ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
// + Die Portierung der Software (oder Teile davon) auf andere Systeme (ausser der Hardware von www.mikrokopter.de) ist nur
// + mit unserer Zustimmung zulässig
// ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
// + Die Funktion printf_P() unterliegt ihrer eigenen Lizenz und ist hiervon nicht betroffen
// ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
// + Redistributions of source code (with or without modifications) must retain the above copyright notice,
// + this list of conditions and the following disclaimer.
// + * Neither the name of the copyright holders nor the names of contributors may be used to endorse or promote products derived
// + from this software without specific prior written permission.
// + * The use of this project (hardware, software, binary files, sources and documentation) is only permittet
// + for non-commercial use (directly or indirectly)
// + Commercial use (for excample: selling of MikroKopters, selling of PCBs, assembly, ...) is only permitted
// + with our written permission
// + * If sources or documentations are redistributet on other webpages, out webpage (http://www.MikroKopter.de) must be
// + clearly linked as origin
// + * porting to systems other than hardware from www.mikrokopter.de is not allowed
// + THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
// + AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
// + IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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// + ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
// + POSSIBILITY OF SUCH DAMAGE.
// ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
#include <avr/io.h>
#include <avr/interrupt.h>
#include <avr/pgmspace.h>
#include "analog.h"
#include "sensors.h"
// for Delay functions
#include "timer0.h"
// For DebugOut
#include "uart0.h"
// For reading and writing acc. meter offsets.
#include "eeprom.h"
/*
* For each A/D conversion cycle, each analog channel is sampled a number of times
* (see array channelsForStates), and the results for each channel are summed.
* Here are those for the gyros and the acc. meters. They are not zero-offset.
* They are exported in the analog.h file - but please do not use them! The only
* reason for the export is that the ENC-03_FC1.3 modules needs them for calibrating
* the offsets with the DAC.
*/
volatile int16_t rawGyroSum[3];
volatile int16_t acc[3];
volatile int16_t filteredAcc[2]={0,0};
/*
* These 4 exported variables are zero-offset. The "PID" ones are used
* in the attitude control as rotation rates. The "ATT" ones are for
* integration to angles.
*/
volatile int16_t gyro_PID[2];
volatile int16_t gyro_ATT[2];
volatile int16_t gyroD[2];
volatile int16_t yawGyro;
/*
* Offset values. These are the raw gyro and acc. meter sums when the copter is
* standing still. They are used for adjusting the gyro and acc. meter values
* to be centered on zero.
*/
volatile int16_t gyroOffset[3] = {
512 * GYRO_SUMMATION_FACTOR_PITCHROLL,
512 * GYRO_SUMMATION_FACTOR_PITCHROLL,
512 * GYRO_SUMMATION_FACTOR_YAW
};
volatile int16_t accOffset[3] = {
512 * ACC_SUMMATION_FACTOR_PITCHROLL,
512 * ACC_SUMMATION_FACTOR_PITCHROLL,
512 * ACC_SUMMATION_FACTOR_Z
};
/*
* This allows some experimentation with the gyro filters.
* Should be replaced by #define's later on...
*/
volatile uint8_t GYROS_PID_FILTER;
volatile uint8_t GYROS_ATT_FILTER;
volatile uint8_t GYROS_D_FILTER;
volatile uint8_t ACC_FILTER;
/*
* Air pressure
*/
volatile uint8_t rangewidth = 106;
// Direct from sensor, irrespective of range.
// volatile uint16_t rawAirPressure;
// Value of 2 samples, with range.
volatile uint16_t simpleAirPressure;
// Value of AIRPRESSURE_SUMMATION_FACTOR samples, with range, filtered.
volatile int32_t filteredAirPressure;
// Partial sum of AIRPRESSURE_SUMMATION_FACTOR samples.
volatile int32_t airPressureSum;
// The number of samples summed into airPressureSum so far.
volatile uint8_t pressureMeasurementCount;
/*
* Battery voltage, in units of: 1k/11k / 3V * 1024 = 31.03 per volt.
* That is divided by 3 below, for a final 10.34 per volt.
* So the initial value of 100 is for 9.7 volts.
*/
volatile int16_t UBat = 100;
/*
* Control and status.
*/
volatile uint16_t ADCycleCount = 0;
volatile uint8_t analogDataReady = 1;
/*
* Experiment: Measuring vibration-induced sensor noise.
*/
volatile uint16_t gyroNoisePeak[2];
volatile uint16_t accNoisePeak[2];
// ADC channels
#define AD_GYRO_YAW 0
#define AD_GYRO_ROLL 1
#define AD_GYRO_PITCH 2
#define AD_AIRPRESSURE 3
#define AD_UBAT 4
#define AD_ACC_Z 5
#define AD_ACC_ROLL 6
#define AD_ACC_PITCH 7
/*
* Table of AD converter inputs for each state.
* The number of samples summed for each channel is equal to
* the number of times the channel appears in the array.
* The max. number of samples that can be taken in 2 ms is:
* 20e6 / 128 / 13 / (1/2e-3) = 24. Since the main control
* loop needs a little time between reading AD values and
* re-enabling ADC, the real limit is (how much?) lower.
* The acc. sensor is sampled even if not used - or installed
* at all. The cost is not significant.
*/
const uint8_t channelsForStates[] PROGMEM = {
AD_GYRO_PITCH,
AD_GYRO_ROLL,
AD_GYRO_YAW,
AD_ACC_PITCH,
AD_ACC_ROLL,
AD_AIRPRESSURE,
AD_GYRO_PITCH,
AD_GYRO_ROLL,
AD_ACC_Z, // at 8, measure Z acc.
AD_GYRO_PITCH,
AD_GYRO_ROLL,
AD_GYRO_YAW, // at 11, finish yaw gyro
AD_ACC_PITCH, // at 12, finish pitch axis acc.
AD_ACC_ROLL, // at 13, finish roll axis acc.
AD_AIRPRESSURE, // at 14, finish air pressure.
AD_GYRO_PITCH, // at 15, finish pitch gyro
AD_GYRO_ROLL, // at 16, finish roll gyro
AD_UBAT // at 17, measure battery.
};
// Feature removed. Could be reintroduced later - but should work for all gyro types then.
// uint8_t GyroDefectPitch = 0, GyroDefectRoll = 0, GyroDefectYaw = 0;
void analog_init(void) {
uint8_t sreg = SREG;
// disable all interrupts before reconfiguration
cli();
//ADC0 ... ADC7 is connected to PortA pin 0 ... 7
DDRA = 0x00;
PORTA = 0x00;
// Digital Input Disable Register 0
// Disable digital input buffer for analog adc_channel pins
DIDR0 = 0xFF;
// external reference, adjust data to the right
ADMUX &= ~((1 << REFS1)|(1 << REFS0)|(1 << ADLAR));
// set muxer to ADC adc_channel 0 (0 to 7 is a valid choice)
ADMUX = (ADMUX & 0xE0) | AD_GYRO_PITCH;
//Set ADC Control and Status Register A
//Auto Trigger Enable, Prescaler Select Bits to Division Factor 128, i.e. ADC clock = SYSCKL/128 = 156.25 kHz
ADCSRA = (0<<ADEN)|(0<<ADSC)|(0<<ADATE)|(1<<ADPS2)|(1<<ADPS1)|(1<<ADPS0)|(0<<ADIE);
//Set ADC Control and Status Register B
//Trigger Source to Free Running Mode
ADCSRB &= ~((1 << ADTS2)|(1 << ADTS1)|(1 << ADTS0));
// Start AD conversion
analog_start();
// restore global interrupt flags
SREG = sreg;
}
void measureNoise(const int16_t sensor, volatile uint16_t* const noiseMeasurement, const uint8_t damping) {
if (sensor > (int16_t)(*noiseMeasurement)) {
*noiseMeasurement = sensor;
} else if (-sensor > (int16_t)(*noiseMeasurement)) {
*noiseMeasurement = -sensor;
} else if (*noiseMeasurement > damping) {
*noiseMeasurement -= damping;
} else {
*noiseMeasurement = 0;
}
}
uint16_t getSimplePressure(int advalue) {
return (uint16_t)OCR0A * (uint16_t)rangewidth + advalue;
}
/*****************************************************
* Interrupt Service Routine for ADC
* Runs at 312.5 kHz or 3.2 µs. When all states are
* processed the interrupt is disabled and further
* AD conversions are stopped.
*****************************************************/
ISR(ADC_vect) {
static uint8_t ad_channel = AD_GYRO_PITCH, state = 0;
static uint16_t sensorInputs[8] = {0,0,0,0,0,0,0,0};
static uint16_t pressureAutorangingWait = 25;
uint16_t rawAirPressure;
uint8_t i, axis;
int16_t newrange;
// for various filters...
int16_t tempOffsetGyro, tempGyro;
sensorInputs[ad_channel] += ADC;
/*
* Actually we don't need this "switch". We could do all the sampling into the
* sensorInputs array first, and all the processing after the last sample.
*/
switch(state++) {
case 8: // Z acc
if (ACC_REVERSED[Z])
acc[Z] = accOffset[Z] - sensorInputs[AD_ACC_Z];
else
acc[Z] = sensorInputs[AD_ACC_Z] - accOffset[Z];
break;
case 11: // yaw gyro
rawGyroSum[YAW] = sensorInputs[AD_GYRO_YAW];
if (GYRO_REVERSED[YAW])
yawGyro = gyroOffset[YAW] - sensorInputs[AD_GYRO_YAW];
else
yawGyro = sensorInputs[AD_GYRO_YAW] - gyroOffset[YAW];
break;
case 12: // pitch axis acc.
if (ACC_REVERSED[PITCH])
acc[PITCH] = accOffset[PITCH] - sensorInputs[AD_ACC_PITCH];
else
acc[PITCH] = sensorInputs[AD_ACC_PITCH] - accOffset[PITCH];
filteredAcc[PITCH] = (filteredAcc[PITCH] * (ACC_FILTER-1) + acc[PITCH]) / ACC_FILTER;
measureNoise(acc[PITCH], &accNoisePeak[PITCH], 1);
break;
case 13: // roll axis acc.
if (ACC_REVERSED[ROLL])
acc[ROLL] = accOffset[ROLL] - sensorInputs[AD_ACC_ROLL];
else
acc[ROLL] = sensorInputs[AD_ACC_ROLL] - accOffset[ROLL];
filteredAcc[ROLL] = (filteredAcc[ROLL] * (ACC_FILTER-1) + acc[ROLL]) / ACC_FILTER;
measureNoise(acc[ROLL], &accNoisePeak[ROLL], 1);
break;
case 14: // air pressure
if (pressureAutorangingWait) {
//A range switch was done recently. Wait for steadying.
pressureAutorangingWait--;
break;
}
rawAirPressure = sensorInputs[AD_AIRPRESSURE];
if (rawAirPressure < MIN_RAWPRESSURE) {
// value is too low, so decrease voltage on the op amp minus input, making the value higher.
newrange = OCR0A - (MAX_RAWPRESSURE - rawAirPressure) / rangewidth - 1;
if (newrange > MIN_RANGES_EXTRAPOLATION) {
pressureAutorangingWait = (OCR0A - newrange) * AUTORANGE_WAIT_FACTOR;
OCR0A = newrange;
} else {
if (OCR0A) {
OCR0A--;
pressureAutorangingWait = AUTORANGE_WAIT_FACTOR;
}
}
} else if (rawAirPressure > MAX_RAWPRESSURE) {
// value is too high, so increase voltage on the op amp minus input, making the value lower.
// If near the end, make a limited increase
newrange = OCR0A + (rawAirPressure - MIN_RAWPRESSURE) / rangewidth - 1;
if (newrange < MAX_RANGES_EXTRAPOLATION) {
pressureAutorangingWait = (newrange - OCR0A) * AUTORANGE_WAIT_FACTOR;
OCR0A = newrange;
} else {
if (OCR0A<254) {
OCR0A++;
pressureAutorangingWait = AUTORANGE_WAIT_FACTOR;
}
}
}
// Even if the sample is off-range, use it.
simpleAirPressure = getSimplePressure(rawAirPressure);
if (simpleAirPressure < MIN_RANGES_EXTRAPOLATION * rangewidth) {
// Danger: pressure near lower end of range. If the measurement saturates, the
// copter may climb uncontrolled... Simulate a drastic reduction in pressure.
airPressureSum += (int16_t)MIN_RANGES_EXTRAPOLATION * rangewidth + (simpleAirPressure - (int32_t)MIN_RANGES_EXTRAPOLATION * rangewidth) * PRESSURE_EXTRAPOLATION_COEFF;
} else if (simpleAirPressure > MAX_RANGES_EXTRAPOLATION * rangewidth) {
// Danger: pressure near upper end of range. If the measurement saturates, the
// copter may fall uncontrolled... Simulate a drastic increase in pressure.
airPressureSum += (int16_t)MAX_RANGES_EXTRAPOLATION * rangewidth + (simpleAirPressure - (int32_t)MAX_RANGES_EXTRAPOLATION * rangewidth) * PRESSURE_EXTRAPOLATION_COEFF;
} else {
// normal case.
airPressureSum += simpleAirPressure;
}
// 2 samples were added.
pressureMeasurementCount += 2;
if (pressureMeasurementCount == AIRPRESSURE_SUMMATION_FACTOR) {
filteredAirPressure = (filteredAirPressure * (AIRPRESSURE_FILTER-1) + airPressureSum + AIRPRESSURE_FILTER/2) / AIRPRESSURE_FILTER;
pressureMeasurementCount = airPressureSum = 0;
}
// DebugOut.Analog[14] = OCR0A;
// DebugOut.Analog[15] = simpleAirPressure;
DebugOut.Analog[11] = UBat;
DebugOut.Analog[27] = acc[Z];
break;
case 15:
case 16: // pitch or roll gyro.
axis = state - 16;
tempGyro = rawGyroSum[axis] = sensorInputs[AD_GYRO_PITCH - axis];
// DebugOut.Analog[6 + 3 * axis ] = tempGyro;
/*
* Process the gyro data for the PID controller.
*/
// 1) Extrapolate: Near the ends of the range, we boost the input significantly. This simulates a
// gyro with a wider range, and helps counter saturation at full control.
if (staticParams.GlobalConfig & CFG_ROTARY_RATE_LIMITER) {
if (tempGyro < SENSOR_MIN_PITCHROLL) {
tempGyro = tempGyro * EXTRAPOLATION_SLOPE - EXTRAPOLATION_LIMIT;
}
else if (tempGyro > SENSOR_MAX_PITCHROLL) {
tempGyro = (tempGyro - SENSOR_MAX_PITCHROLL) * EXTRAPOLATION_SLOPE + SENSOR_MAX_PITCHROLL;
}
}
// 2) Apply sign and offset, scale before filtering.
if (GYRO_REVERSED[axis]) {
tempOffsetGyro = (gyroOffset[axis] - tempGyro) * GYRO_FACTOR_PITCHROLL;
} else {
tempOffsetGyro = (tempGyro - gyroOffset[axis]) * GYRO_FACTOR_PITCHROLL;
}
// 3) Scale and filter.
tempOffsetGyro = (gyro_PID[axis] * (GYROS_PID_FILTER-1) + tempOffsetGyro) / GYROS_PID_FILTER;
// 4) Measure noise.
measureNoise(tempOffsetGyro, &gyroNoisePeak[axis], GYRO_NOISE_MEASUREMENT_DAMPING);
// 5) Differential measurement.
gyroD[axis] = (gyroD[axis] * (GYROS_D_FILTER-1) + (tempOffsetGyro - gyro_PID[axis])) / GYROS_D_FILTER;
// 6) Done.
gyro_PID[axis] = tempOffsetGyro;
/*
* Now process the data for attitude angles.
*/
tempGyro = rawGyroSum[axis];
// 1) Apply sign and offset, scale before filtering.
if (GYRO_REVERSED[axis]) {
tempOffsetGyro = (gyroOffset[axis] - tempGyro) * GYRO_FACTOR_PITCHROLL;
} else {
tempOffsetGyro = (tempGyro - gyroOffset[axis]) * GYRO_FACTOR_PITCHROLL;
}
// 2) Filter.
gyro_ATT[axis] = (gyro_ATT[axis] * (GYROS_ATT_FILTER-1) + tempOffsetGyro) / GYROS_ATT_FILTER;
break;
case 17:
// Battery. The measured value is: (V * 1k/11k)/3v * 1024 = 31.03 counts per volt (max. measurable is 33v).
// This is divided by 3 --> 10.34 counts per volt.
UBat = (3 * UBat + sensorInputs[AD_UBAT] / 3) / 4;
analogDataReady = 1; // mark
ADCycleCount++;
// Stop the sampling. Cycle is over.
state = 0;
for (i=0; i<8; i++) {
sensorInputs[i] = 0;
}
break;
default: {} // do nothing.
}
// set up for next state.
ad_channel = pgm_read_byte(&channelsForStates[state]);
// ad_channel = channelsForStates[state];
// set adc muxer to next ad_channel
ADMUX = (ADMUX & 0xE0) | ad_channel;
// after full cycle stop further interrupts
if(state) analog_start();
}
void analog_calibrate(void) {
#define GYRO_OFFSET_CYCLES 32
uint8_t i, axis;
int32_t deltaOffsets[3] = {0,0,0};
// Set the filters... to be removed again, once some good settings are found.
GYROS_PID_FILTER = (dynamicParams.UserParams[4] & 0b00000011) + 1;
GYROS_ATT_FILTER = ((dynamicParams.UserParams[4] & 0b00001100) >> 2) + 1;
GYROS_D_FILTER = ((dynamicParams.UserParams[4] & 0b00110000) >> 4) + 1;
ACC_FILTER = ((dynamicParams.UserParams[4] & 0b11000000) >> 6) + 1;
gyro_calibrate();
// determine gyro bias by averaging (requires that the copter does not rotate around any axis!)
for(i=0; i < GYRO_OFFSET_CYCLES; i++) {
Delay_ms_Mess(20);
for (axis=PITCH; axis<=YAW; axis++) {
deltaOffsets[axis] += rawGyroSum[axis];
}
}
for (axis=PITCH; axis<=YAW; axis++) {
gyroOffset[axis] = (deltaOffsets[axis] + GYRO_OFFSET_CYCLES/2) / GYRO_OFFSET_CYCLES;
DebugOut.Analog[20+axis] = gyroOffset[axis];
}
// Noise is relative to offset. So, reset noise measurements when changing offsets.
gyroNoisePeak[PITCH] = gyroNoisePeak[ROLL] = 0;
accOffset[PITCH] = GetParamWord(PID_ACC_PITCH);
accOffset[ROLL] = GetParamWord(PID_ACC_ROLL);
accOffset[Z] = GetParamWord(PID_ACC_Z);
// Rough estimate. Hmm no nothing happens at calibration anyway.
// airPressureSum = simpleAirPressure * (AIRPRESSURE_SUMMATION_FACTOR/2);
// pressureMeasurementCount = 0;
// Experiment!
// filteredAirPressureOffset = filteredAirPressure - 1000L;
Delay_ms_Mess(100);
}
/*
* Find acc. offsets for a neutral reading, and write them to EEPROM.
* Does not (!} update the local variables. This must be done with a
* call to analog_calibrate() - this always (?) is done by the caller
* anyway. There would be nothing wrong with updating the variables
* directly from here, though.
*/
void analog_calibrateAcc(void) {
#define ACC_OFFSET_CYCLES 10
uint8_t i, axis;
int32_t deltaOffset[3] = {0,0,0};
int16_t filteredDelta;
// int16_t pressureDiff, savedRawAirPressure;
for(i=0; i < ACC_OFFSET_CYCLES; i++) {
Delay_ms_Mess(10);
for (axis=PITCH; axis<=YAW; axis++) {
deltaOffset[axis] += acc[axis];
}
}
for (axis=PITCH; axis<=YAW; axis++) {
filteredDelta = (deltaOffset[axis] + ACC_OFFSET_CYCLES / 2) / ACC_OFFSET_CYCLES;
accOffset[axis] += ACC_REVERSED[axis] ? -filteredDelta : filteredDelta;
}
// Save ACC neutral settings to eeprom
SetParamWord(PID_ACC_PITCH, accOffset[PITCH]);
SetParamWord(PID_ACC_ROLL, accOffset[ROLL]);
SetParamWord(PID_ACC_Z, accOffset[Z]);
// Noise is relative to offset. So, reset noise measurements when
// changing offsets.
accNoisePeak[PITCH] = accNoisePeak[ROLL] = 0;
// Setting offset values has an influence in the analog.c ISR
// Therefore run measurement for 100ms to achive stable readings
Delay_ms_Mess(100);
// Set the feedback so that air pressure ends up in the middle of the range.
// (raw pressure high --> OCR0A also high...)
// OCR0A += (rawAirPressure - 512) / rangewidth;
// Delay_ms_Mess(500);
/*
pressureDiff = 0;
// DebugOut.Analog[16] = rawAirPressure;
#define PRESSURE_CAL_CYCLE_COUNT 2
for (i=0; i<PRESSURE_CAL_CYCLE_COUNT; i++) {
savedRawAirPressure = rawAirPressure;
OCR0A++;
Delay_ms_Mess(200);
// raw pressure will decrease.
pressureDiff += (savedRawAirPressure - rawAirPressure);
savedRawAirPressure = rawAirPressure;
OCR0A--;
Delay_ms_Mess(200);
// raw pressure will increase.
pressureDiff += (rawAirPressure - savedRawAirPressure);
}
// DebugOut.Analog[16] =
rangewidth = (pressureDiff + PRESSURE_CAL_CYCLE_COUNT * 2 - 1) / (PRESSURE_CAL_CYCLE_COUNT * 2);
*/
}