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#include "temp.h"
/** \file
\brief Manage temperature sensors
\note \b ALL temperatures are stored as 14.2 fixed point in teacup, so we have a range of 0 - 16383.75 celsius and a precision of 0.25 celsius. That includes the ThermistorTable, which is why you can't copy and paste one from other firmwares which don't do this.
*/
#include <stdlib.h>
#ifndef SIMULATOR
#include <avr/eeprom.h>
#include <avr/pgmspace.h>
#endif
#include "simulator.h"
#include "arduino.h"
#include "debug.h"
#ifndef EXTRUDER
#include "sersendf.h"
#endif
#include "heater.h"
#ifdef TEMP_INTERCOM
#include "intercom.h"
#endif
#ifdef TEMP_MAX6675
#endif
#ifdef TEMP_THERMISTOR
#include "analog.h"
#include "ThermistorTable.h"
#endif
#ifdef TEMP_AD595
#include "analog.h"
#endif
typedef enum {
PRESENT,
TCOPEN
} temp_flags_enum;
/// holds metadata for each temperature sensor
typedef struct {
temp_type_t temp_type; ///< type of sensor
uint8_t temp_pin; ///< pin that sensor is on
heater_t heater; ///< associated heater if any
uint8_t additional; ///< additional, sensor type specifc config
} temp_sensor_definition_t;
#undef DEFINE_TEMP_SENSOR
/// help build list of sensors from entries in config.h
#ifndef SIMULATOR
#define DEFINE_TEMP_SENSOR(name, type, pin, additional) { (type), (pin ## _ADC), (HEATER_ ## name), (additional) },
#else
#define DEFINE_TEMP_SENSOR(name, type, pin, additional) { (type), (TEMP_SENSOR_ ## name), (HEATER_ ## name), (additional) },
#endif
static const temp_sensor_definition_t temp_sensors[NUM_TEMP_SENSORS] =
{
#include "config_wrapper.h"
};
#undef DEFINE_TEMP_SENSOR
/// this struct holds the runtime sensor data- read temperatures, targets, etc
struct {
temp_flags_enum temp_flags; ///< flags
uint16_t last_read_temp; ///< last received reading
uint16_t target_temp; ///< manipulate attached heater to attempt to achieve this value
uint16_t temp_residency; ///< how long have we been close to target temperature in temp ticks?
uint16_t next_read_time; ///< how long until we can read this sensor again?
} temp_sensors_runtime[NUM_TEMP_SENSORS];
/// Set up temp sensors.
void temp_init() {
temp_sensor_t i;
for (i = 0; i < NUM_TEMP_SENSORS; i++) {
switch(temp_sensors[i].temp_type) {
#ifdef TEMP_MAX6675
case TT_MAX6675:
WRITE(SS, 1); // Turn sensor off.
SET_OUTPUT(SS);
// Intentionally no break, we might have more than one sensor type.
#endif
#ifdef TEMP_THERMISTOR
// handled by analog_init()
/* case TT_THERMISTOR:
break;*/
#endif
#ifdef TEMP_AD595
// handled by analog_init()
/* case TT_AD595:
break;*/
#endif
#ifdef TEMP_INTERCOM
case TT_INTERCOM:
// Enable the RS485 transceiver
SET_OUTPUT(RX_ENABLE_PIN);
SET_OUTPUT(TX_ENABLE_PIN);
WRITE(RX_ENABLE_PIN,0);
disable_transmit();
intercom_init();
send_temperature(0, 0);
// Intentionally no break.
#endif
default: /* prevent compiler warning */
break;
}
}
}
/// called every 10ms from clock.c - check all temp sensors that are ready for checking
void temp_sensor_tick() {
temp_sensor_t i = 0;
for (; i < NUM_TEMP_SENSORS; i++) {
if (temp_sensors_runtime[i].next_read_time) {
temp_sensors_runtime[i].next_read_time--;
}
else {
uint16_t temp = 0;
//time to deal with this temp sensor
switch(temp_sensors[i].temp_type) {
#ifdef TEMP_MAX6675
case TT_MAX6675:
#ifdef PRR
PRR &= ~MASK(PRSPI);
#elif defined PRR0
PRR0 &= ~MASK(PRSPI);
#endif
SPCR = MASK(MSTR) | MASK(SPE) | MASK(SPR0);
// enable TT_MAX6675
WRITE(SS, 0);
// No delay required, see
// https://github.com/triffid/Teacup_Firmware/issues/22
// read MSB
SPDR = 0;
for (;(SPSR & MASK(SPIF)) == 0;);
temp = SPDR;
temp <<= 8;
// read LSB
SPDR = 0;
for (;(SPSR & MASK(SPIF)) == 0;);
temp |= SPDR;
// disable TT_MAX6675
WRITE(SS, 1);
temp_sensors_runtime[i].temp_flags = 0;
if ((temp & 0x8002) == 0) {
// got "device id"
temp_sensors_runtime[i].temp_flags |= PRESENT;
if (temp & 4) {
// thermocouple open
temp_sensors_runtime[i].temp_flags |= TCOPEN;
}
else {
temp = temp >> 3;
}
}
// this number depends on how frequently temp_sensor_tick is called. the MAX6675 can give a reading every 0.22s, so set this to about 250ms
temp_sensors_runtime[i].next_read_time = 25;
break;
#endif /* TEMP_MAX6675 */
#ifdef TEMP_THERMISTOR
case TT_THERMISTOR:
do {
uint8_t j, table_num;
//Read current temperature
temp = analog_read(i);
// for thermistors the thermistor table number is in the additional field
table_num = temp_sensors[i].additional;
//Calculate real temperature based on lookup table
for (j = 1; j < NUMTEMPS; j++) {
if (pgm_read_word(&(temptable[table_num][j][0])) > temp) {
// Thermistor table is already in 14.2 fixed point
#ifndef EXTRUDER
if (DEBUG_PID && (debug_flags & DEBUG_PID))
sersendf_P(PSTR("pin:%d Raw ADC:%d table entry: %d"),temp_sensors[i].temp_pin,temp,j);
#endif
// Linear interpolating temperature value
// y = ((x - x₀)y₁ + (x₁-x)y₀ ) / (x₁ - x₀)
// y = temp
// x = ADC reading
// x₀= temptable[j-1][0]
// x₁= temptable[j][0]
// y₀= temptable[j-1][1]
// y₁= temptable[j][1]
// y =
// Wikipedia's example linear interpolation formula.
temp = (
// ((x - x₀)y₁
((uint32_t)temp - pgm_read_word(&(temptable[table_num][j-1][0]))) * pgm_read_word(&(temptable[table_num][j][1]))
// +
+
// (x₁-x)
(pgm_read_word(&(temptable[table_num][j][0])) - (uint32_t)temp)
// y₀ )
* pgm_read_word(&(temptable[table_num][j-1][1])))
// /
/
// (x₁ - x₀)
(pgm_read_word(&(temptable[table_num][j][0])) - pgm_read_word(&(temptable[table_num][j-1][0])));
#ifndef EXTRUDER
if (DEBUG_PID && (debug_flags & DEBUG_PID))
sersendf_P(PSTR(" temp:%d.%d"),temp/4,(temp%4)*25);
#endif
break;
}
}
#ifndef EXTRUDER
if (DEBUG_PID && (debug_flags & DEBUG_PID))
sersendf_P(PSTR(" Sensor:%d\n"),i);
#endif
//Clamp for overflows
if (j == NUMTEMPS)
temp = temptable[table_num][NUMTEMPS-1][1];
temp_sensors_runtime[i].next_read_time = 0;
} while (0);
break;
#endif /* TEMP_THERMISTOR */
#ifdef TEMP_AD595
case TT_AD595:
temp = analog_read(i);
// convert
// >>8 instead of >>10 because internal temp is stored as 14.2 fixed point
temp = (temp * 500L) >> 8;
temp_sensors_runtime[i].next_read_time = 0;
break;
#endif /* TEMP_AD595 */
#ifdef TEMP_PT100
case TT_PT100:
#warning TODO: PT100 code
break;
#endif /* TEMP_PT100 */
#ifdef TEMP_INTERCOM
case TT_INTERCOM:
temp = read_temperature(temp_sensors[i].temp_pin);
temp_sensors_runtime[i].next_read_time = 25;
break;
#endif /* TEMP_INTERCOM */
#ifdef TEMP_DUMMY
case TT_DUMMY:
temp = temp_sensors_runtime[i].last_read_temp;
if (temp_sensors_runtime[i].target_temp > temp)
temp++;
else if (temp_sensors_runtime[i].target_temp < temp)
temp--;
temp_sensors_runtime[i].next_read_time = 0;
break;
#endif /* TEMP_DUMMY */
default: /* prevent compiler warning */
break;
}
/* Exponentially Weighted Moving Average alpha constant for smoothing
noisy sensors. Instrument Engineer's Handbook, 4th ed, Vol 2 p126
says values of 0.05 to 0.1 for TEMP_EWMA are typical. */
#ifndef TEMP_EWMA
#define TEMP_EWMA 1.0
#endif
#define EWMA_SCALE 1024L
#define EWMA_ALPHA ((long) (TEMP_EWMA * EWMA_SCALE))
temp_sensors_runtime[i].last_read_temp = (uint16_t) ((EWMA_ALPHA * temp +
(EWMA_SCALE-EWMA_ALPHA) * temp_sensors_runtime[i].last_read_temp
) / EWMA_SCALE);
}
if (labs((int16_t)(temp_sensors_runtime[i].last_read_temp - temp_sensors_runtime[i].target_temp)) < (TEMP_HYSTERESIS*4)) {
if (temp_sensors_runtime[i].temp_residency < (TEMP_RESIDENCY_TIME*120))
temp_sensors_runtime[i].temp_residency++;
}
else {
// Deal with flakey sensors which occasionally report a wrong value
// by setting residency back, but not entirely to zero.
if (temp_sensors_runtime[i].temp_residency > 10)
temp_sensors_runtime[i].temp_residency -= 10;
else
temp_sensors_runtime[i].temp_residency = 0;
}
if (temp_sensors[i].heater < NUM_HEATERS) {
heater_tick(temp_sensors[i].heater, temp_sensors[i].temp_type, temp_sensors_runtime[i].last_read_temp, temp_sensors_runtime[i].target_temp);
}
if (DEBUG_PID && (debug_flags & DEBUG_PID))
sersendf_P(PSTR("DU temp: {%d %d %d.%d}"), i,
temp_sensors_runtime[i].last_read_temp,
temp_sensors_runtime[i].last_read_temp / 4,
(temp_sensors_runtime[i].last_read_temp & 0x03) * 25);
}
if (DEBUG_PID && (debug_flags & DEBUG_PID))
sersendf_P(PSTR("\n"));
}
/**
* Report whether all temp sensors in use are reading their target
* temperatures. Used for M116 and friends.
*/
uint8_t temp_achieved() {
temp_sensor_t i;
uint8_t all_ok = 255;
for (i = 0; i < NUM_TEMP_SENSORS; i++) {
if (temp_sensors_runtime[i].target_temp > 0 &&
temp_sensors_runtime[i].temp_residency < (TEMP_RESIDENCY_TIME*100))
all_ok = 0;
}
return all_ok;
}
/// specify a target temperature
/// \param index sensor to set a target for
/// \param temperature target temperature to aim for
void temp_set(temp_sensor_t index, uint16_t temperature) {
if (index >= NUM_TEMP_SENSORS)
return;
// only reset residency if temp really changed
if (temp_sensors_runtime[index].target_temp != temperature) {
temp_sensors_runtime[index].target_temp = temperature;
temp_sensors_runtime[index].temp_residency = 0;
#ifdef TEMP_INTERCOM
if (temp_sensors[index].temp_type == TT_INTERCOM)
send_temperature(temp_sensors[index].temp_pin, temperature);
#endif
}
}
/// return most recent reading for a sensor
/// \param index sensor to read
uint16_t temp_get(temp_sensor_t index) {
if (index >= NUM_TEMP_SENSORS)
return 0;
return temp_sensors_runtime[index].last_read_temp;
}
// extruder doesn't have sersendf_P
#ifndef EXTRUDER
static void single_temp_print(temp_sensor_t index) {
uint8_t c = (temp_sensors_runtime[index].last_read_temp & 3) * 25;
sersendf_P(PSTR("%u.%u"), temp_sensors_runtime[index].last_read_temp >> 2, c);
}
/// send temperatures to host
/// \param index sensor value to send
void temp_print(temp_sensor_t index) {
if (index == TEMP_SENSOR_none) { // standard behaviour
#ifdef HEATER_EXTRUDER
sersendf_P(PSTR("T:"));
single_temp_print(HEATER_EXTRUDER);
#endif
#ifdef HEATER_BED
sersendf_P(PSTR(" B:"));
single_temp_print(HEATER_BED);
#endif
}
else {
if (index >= NUM_TEMP_SENSORS)
return;
sersendf_P(PSTR("T[%su]:"), index);
single_temp_print(index);
}
}
#endif
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