Merge pull request #6272 from thinkyhead/rc_adc_variable_rate

Make ADC sensor reading frequency adjustable
This commit is contained in:
Scott Lahteine 2017-04-13 12:49:31 -05:00 committed by GitHub
commit 02fca543bb
3 changed files with 129 additions and 119 deletions

View file

@ -91,28 +91,6 @@ enum EndstopEnum {
Z2_MAX
};
/**
* Temperature
* Stages in the ISR loop
*/
enum TempState {
PrepareTemp_0,
MeasureTemp_0,
PrepareTemp_BED,
MeasureTemp_BED,
PrepareTemp_1,
MeasureTemp_1,
PrepareTemp_2,
MeasureTemp_2,
PrepareTemp_3,
MeasureTemp_3,
PrepareTemp_4,
MeasureTemp_4,
Prepare_FILWIDTH,
Measure_FILWIDTH,
StartupDelay // Startup, delay initial temp reading a tiny bit so the hardware can settle
};
#if ENABLED(EMERGENCY_PARSER)
enum e_parser_state {
state_RESET,

View file

@ -24,8 +24,6 @@
* temperature.cpp - temperature control
*/
#include "Marlin.h"
#include "ultralcd.h"
#include "temperature.h"
@ -1538,8 +1536,8 @@ void Temperature::isr() {
CBI(TIMSK0, OCIE0B); //Disable Temperature ISR
sei();
static uint8_t temp_count = 0;
static TempState temp_state = StartupDelay;
static int8_t temp_count = -1;
static ADCSensorState adc_sensor_state = StartupDelay;
static uint8_t pwm_count = _BV(SOFT_PWM_SCALE);
// avoid multiple loads of pwm_count
uint8_t pwm_count_tmp = pwm_count;
@ -1812,6 +1810,22 @@ void Temperature::isr() {
#endif // SLOW_PWM_HEATERS
//
// Update lcd buttons 488 times per second
//
static bool do_buttons;
if ((do_buttons ^= true)) lcd_buttons_update();
/**
* One sensor is sampled on every other call of the ISR.
* Each sensor is read 16 (OVERSAMPLENR) times, taking the average.
*
* On each Prepare pass, ADC is started for a sensor pin.
* On the next pass, the ADC value is read and accumulated.
*
* This gives each ADC 0.9765ms to charge up.
*/
#define SET_ADMUX_ADCSRA(pin) ADMUX = _BV(REFS0) | (pin & 0x07); SBI(ADCSRA, ADSC)
#ifdef MUX5
#define START_ADC(pin) if (pin > 7) ADCSRB = _BV(MUX5); else ADCSRB = 0; SET_ADMUX_ADCSRA(pin)
@ -1819,122 +1833,94 @@ void Temperature::isr() {
#define START_ADC(pin) ADCSRB = 0; SET_ADMUX_ADCSRA(pin)
#endif
// Prepare or measure a sensor, each one every 14th frame
switch (temp_state) {
case PrepareTemp_0:
switch (adc_sensor_state) {
case SensorsReady: {
// All sensors have been read. Stay in this state for a few
// ISRs to save on calls to temp update/checking code below.
constexpr int extra_loops = MIN_ADC_ISR_LOOPS - (int)SensorsReady;
static uint8_t delay_count = 0;
if (extra_loops > 0) {
if (delay_count == 0) delay_count = extra_loops; // Init this delay
if (--delay_count) // While delaying...
adc_sensor_state = (ADCSensorState)(int(SensorsReady) - 1); // retain this state (else, next state will be 0)
break;
}
else
adc_sensor_state = (ADCSensorState)0; // Fall-through to start first sensor now
}
#if HAS_TEMP_0
case PrepareTemp_0:
START_ADC(TEMP_0_PIN);
#endif
lcd_buttons_update();
temp_state = MeasureTemp_0;
break;
case MeasureTemp_0:
#if HAS_TEMP_0
raw_temp_value[0] += ADC;
#endif
temp_state = PrepareTemp_BED;
break;
case PrepareTemp_BED:
#if HAS_TEMP_BED
START_ADC(TEMP_BED_PIN);
#endif
lcd_buttons_update();
temp_state = MeasureTemp_BED;
#if HAS_TEMP_BED
case PrepareTemp_BED:
START_ADC(TEMP_BED_PIN);
break;
case MeasureTemp_BED:
#if HAS_TEMP_BED
raw_temp_bed_value += ADC;
#endif
temp_state = PrepareTemp_1;
break;
case PrepareTemp_1:
#if HAS_TEMP_1
START_ADC(TEMP_1_PIN);
#endif
lcd_buttons_update();
temp_state = MeasureTemp_1;
#if HAS_TEMP_1
case PrepareTemp_1:
START_ADC(TEMP_1_PIN);
break;
case MeasureTemp_1:
#if HAS_TEMP_1
raw_temp_value[1] += ADC;
#endif
temp_state = PrepareTemp_2;
break;
case PrepareTemp_2:
#if HAS_TEMP_2
START_ADC(TEMP_2_PIN);
#endif
lcd_buttons_update();
temp_state = MeasureTemp_2;
#if HAS_TEMP_2
case PrepareTemp_2:
START_ADC(TEMP_2_PIN);
break;
case MeasureTemp_2:
#if HAS_TEMP_2
raw_temp_value[2] += ADC;
#endif
temp_state = PrepareTemp_3;
break;
case PrepareTemp_3:
#if HAS_TEMP_3
START_ADC(TEMP_3_PIN);
#endif
lcd_buttons_update();
temp_state = MeasureTemp_3;
#if HAS_TEMP_3
case PrepareTemp_3:
START_ADC(TEMP_3_PIN);
break;
case MeasureTemp_3:
#if HAS_TEMP_3
raw_temp_value[3] += ADC;
#endif
temp_state = PrepareTemp_4;
break;
case PrepareTemp_4:
#if HAS_TEMP_4
START_ADC(TEMP_4_PIN);
#endif
lcd_buttons_update();
temp_state = MeasureTemp_4;
#if HAS_TEMP_4
case PrepareTemp_4:
START_ADC(TEMP_4_PIN);
break;
case MeasureTemp_4:
#if HAS_TEMP_4
raw_temp_value[4] += ADC;
#endif
temp_state = Prepare_FILWIDTH;
break;
case Prepare_FILWIDTH:
#if ENABLED(FILAMENT_WIDTH_SENSOR)
START_ADC(FILWIDTH_PIN);
#endif
lcd_buttons_update();
temp_state = Measure_FILWIDTH;
#if ENABLED(FILAMENT_WIDTH_SENSOR)
case Prepare_FILWIDTH:
START_ADC(FILWIDTH_PIN);
break;
case Measure_FILWIDTH:
#if ENABLED(FILAMENT_WIDTH_SENSOR)
// raw_filwidth_value += ADC; //remove to use an IIR filter approach
if (ADC > 102) { //check that ADC is reading a voltage > 0.5 volts, otherwise don't take in the data.
raw_filwidth_value -= (raw_filwidth_value >> 7); //multiply raw_filwidth_value by 127/128
raw_filwidth_value += ((unsigned long)ADC << 7); //add new ADC reading
if (ADC > 102) { // Make sure ADC is reading > 0.5 volts, otherwise don't read.
raw_filwidth_value -= (raw_filwidth_value >> 7); // Subtract 1/128th of the raw_filwidth_value
raw_filwidth_value += ((unsigned long)ADC << 7); // Add new ADC reading, scaled by 128
}
break;
#endif
temp_state = PrepareTemp_0;
temp_count++;
break;
case StartupDelay:
temp_state = PrepareTemp_0;
break;
case StartupDelay: break;
// default:
// SERIAL_ERROR_START;
// SERIAL_ERRORLNPGM("Temp measurement error!");
// break;
} // switch(temp_state)
} // switch(adc_sensor_state)
if (temp_count >= OVERSAMPLENR) { // 10 * 16 * 1/(16000000/64/256) = 164ms.
if (!adc_sensor_state && ++temp_count >= OVERSAMPLENR) { // 10 * 16 * 1/(16000000/64/256) = 164ms.
temp_count = 0;
@ -1998,6 +1984,9 @@ void Temperature::isr() {
} // temp_count >= OVERSAMPLENR
// Go to the next state, up to SensorsReady
adc_sensor_state = (ADCSensorState)((int(adc_sensor_state) + 1) % int(StartupDelay));
#if ENABLED(BABYSTEPPING)
LOOP_XYZ(axis) {
int curTodo = babystepsTodo[axis]; //get rid of volatile for performance

View file

@ -50,6 +50,49 @@
#define EXTRUDER_IDX active_extruder
#endif
/**
* States for ADC reading in the ISR
*/
enum ADCSensorState {
#if HAS_TEMP_0
PrepareTemp_0,
MeasureTemp_0,
#endif
#if HAS_TEMP_1
PrepareTemp_1,
MeasureTemp_1,
#endif
#if HAS_TEMP_2
PrepareTemp_2,
MeasureTemp_2,
#endif
#if HAS_TEMP_3
PrepareTemp_3,
MeasureTemp_3,
#endif
#if HAS_TEMP_4
PrepareTemp_4,
MeasureTemp_4,
#endif
#if HAS_TEMP_BED
PrepareTemp_BED,
MeasureTemp_BED,
#endif
#if ENABLED(FILAMENT_WIDTH_SENSOR)
Prepare_FILWIDTH,
Measure_FILWIDTH,
#endif
SensorsReady, // Temperatures ready. Delay the next round of readings to let ADC pins settle.
StartupDelay // Startup, delay initial temp reading a tiny bit so the hardware can settle
};
// Minimum number of Temperature::ISR loops between sensor readings.
// Multiplied by 16 (OVERSAMPLENR) to obtain the total time to
// get all oversampled sensor readings
#define MIN_ADC_ISR_LOOPS 10
#define ACTUAL_ADC_SAMPLES max(int(MIN_ADC_ISR_LOOPS), int(SensorsReady))
class Temperature {
public:
@ -74,7 +117,7 @@ class Temperature {
#endif
#if ENABLED(PIDTEMP) || ENABLED(PIDTEMPBED)
#define PID_dT ((OVERSAMPLENR * 12.0)/(F_CPU / 64.0 / 256.0))
#define PID_dT ((OVERSAMPLENR * float(ACTUAL_ADC_SAMPLES)) / (F_CPU / 64.0 / 256.0))
#endif
#if ENABLED(PIDTEMP)