@@ -24,28 +24,30 @@ BUILD_DIR = build
LD_SCRIPT = stm32f042c6_flash.ld
# USER_DEFS user defined macros
USER_DEFS = -D HSI48_VALUE=48000000 -D HSE_VALUE=16000000
# USER_INCLUDES: user defined includes
USER_INCLUDES = -Isystem
# USB_INCLUDES: includes for the usb library
USB_INCLUDES = -Imiddlewares/ST/STM32_USB_Device_Library/Core/Inc
USB_INCLUDES += -Imiddlewares/ST/STM32_USB_Device_Library/Class/CDC/Inc
# USER_CFLAGS: user C flags (enable warnings, enable debug info)
USER_CFLAGS = -Wall -g -ffunction-sections -fno-exceptions -fdata-sections -Os
USER_CFLAGS = -Wall -g -ffunction-sections -fno-exceptions -fdata-sections -Os --function-sections -fno-common
# USER_LDFLAGS: user LD flags
USER_LDFLAGS = -fno-exceptions -ffunction-sections -fno-exceptions -fdata-sections -Wl,--gc-sections
USER_LDFLAGS += --static
# TARGET_DEVICE: device to compile for
TARGET_DEVICE = STM32F042x6
#######################################
# end of user configuration
#
# binaries
CC = arm-none-eabi-gcc
AR = arm-none-eabi-ar
#ifndef CONFIG_H
#define CONFIG_H
// Temperature sensor type
//#define MAX31855_TC_SENSOR
#define MAX31865_RTD_SENSOR
#define MAX31855_TC_SENSOR
//#define MAX31865_RTD_SENSOR
// Virtual serial port transmit rate
#define VCP_TX_FREQ 1000
// Solid-state relay maximum on-time
#define SSR_PERIOD 200
// Interval of PID calculations
#define PID_PERIOD 120
@@ -64,25 +64,28 @@ void display_process(therm_settings_t* s
ssd1306_drawstring(" ", 3, 72);
ssd1306_drawstring(tempstr, 3, 72);
}
if (state_changed) {
ssd1306_drawlogo();
switch(goto_mode) {
case MODE_HEAT:
{
ssd1306_drawstring("-> heat ", 1, 40);
if(set->val.plant_type == PLANT_HEATER)
else
ssd1306_drawstring("-> cool ", 1, 40);
} break;
case MODE_SETUP:
ssd1306_drawstring("-> setup ", 1, 40);
case MODE_RESET:
ssd1306_drawstring("-> reset ", 1, 40);
@@ -92,25 +95,25 @@ void display_process(therm_settings_t* s
ssd1306_drawstring("-> dfu ", 1, 40);
#endif
// Button handler
if(SW_BTN_PRESSED) {
status->state = STATE_PREHEAT;
break;
status->state = STATE_SETP;
status->state = STATE_SETMODE;
status->state = STATE_RESET;
reset_mode = RESET_REBOOT;
#ifdef BOOTLOADER_SHORTCUT
case MODE_BOOTLOADER:
ssd1306_clearscreen();
ssd1306_drawstring("Bootloader Entered", 0, 0);
ssd1306_drawstring("Device won't boot", 2, 0);
ssd1306_drawstring("until reflashed!", 3, 0);
bootloader_enter(); // Resets into bootloader
@@ -125,24 +128,91 @@ void display_process(therm_settings_t* s
goto_mode++;
else if(SW_UP_PRESSED && goto_mode > 0) {
goto_mode--;
// Event Handler
// N/A
case STATE_SETMODE:
// Write text to OLED
// [ therm :: set mode ]
// [ m = ]
ssd1306_drawstring("Control Mode", 0, 40);
if(set->val.control_mode == MODE_PID)
ssd1306_drawstring("PID ", 1, 60);
ssd1306_drawstring("Thermostat", 1, 60);
ssd1306_drawstring("Press to accept", 3, 40);
status->state = STATE_SETPLANTTYPE;
else if (!HAL_GPIO_ReadPin(SW_UP)) {
set->val.control_mode = MODE_PID;
else if(!HAL_GPIO_ReadPin(SW_DOWN)) {
set->val.control_mode = MODE_THERMOSTAT;
case STATE_SETPLANTTYPE:
ssd1306_drawstring("Plant Type", 0, 40);
ssd1306_drawstring("Heater", 1, 60);
ssd1306_drawstring("Cooler", 1, 60);
status->state = STATE_SETBOOTTOBREW;
set->val.plant_type = PLANT_COOLER;
set->val.plant_type = PLANT_HEATER;
case STATE_SETP:
// [ therm :: set p ]
// [ p = 12 ]
ssd1306_drawstring("Proportional", 0, 40);
char tempstr[6];
itoa(set->val.k_p, tempstr, 10);
ssd1306_drawstring("P=", 1, 45);
ssd1306_drawstring(" ", 1, 57);
@@ -369,26 +439,30 @@ void display_process(therm_settings_t* s
if(status->temp >= status->setpoint) {
status->state = STATE_MAINTAIN;
case STATE_MAINTAIN:
// [ therm : ready to brew ]
// [ 30 => 120 C ]
ssd1306_drawstring("Preheated!", 0, 0);
//ssd1306_drawlogo();
ssd1306_drawstring("Precooled!", 0, 0);
draw_setpoint(status);
status->pid_enabled = 1;
status->setpoint = set->val.setpoint_brew;
status->state = STATE_IDLE;
else {
user_input((uint16_t*)&set->val.setpoint_brew);
@@ -80,95 +80,148 @@ int main(void)
// Restore settings from flash memory
flash_restore(&set);
HAL_Delay(2000);
// Soft timers
uint32_t last_ssr_on = 0;
uint32_t last_vcp_tx = 0;
uint32_t last_led = 0;
uint32_t last_pid = 0;
uint32_t last_thermostat = 0;
int16_t ssr_output = 0; // Duty cycle of ssr, 0 to SSR_PERIOD
// Main loop
while(1)
// Process sensor inputs
if(HAL_GetTick() - last_led > 400)
last_led = HAL_GetTick();
if((HAL_GetTick() - last_pid > PID_PERIOD))
if(set.val.control_mode == MODE_PID && (HAL_GetTick() - last_pid > PID_PERIOD))
#ifdef MAX31865_RTD_SENSOR
max31865_readtemp(spi_get(), &set, &status);
#else
max31855_readtemp(spi_get(), &set, &status); // Read MAX31855
if(status.pid_enabled)
// Get ssr output for next time
int16_t power_percent = pid_update(&set, &status, &pid_state);
if(set.val.plant_type == PLANT_HEATER)
power_percent *= -1;
//power-percent is 0-1000?
ssr_output = power_percent; //(((uint32_t)SSR_PERIOD * (uint32_t)10 * (uint32_t)100) * power_percent) / (uint32_t)1000000;
// put ssr output on display
ssd1306_drawstring(" ", 0, 90); //fixme: this is bad, but I can't get the old digits to clear otherwise
itoa(ssr_output, tempstr, 10);
ssd1306_drawstring(tempstr, 0, 90);
ssr_output = 0;
last_pid = HAL_GetTick();
// Kill SSR once the desired on-time has elapsed
if(HAL_GetTick() - last_ssr_on > ssr_output || ssr_output <= 0)
if(set.val.control_mode == MODE_PID && (HAL_GetTick() - last_ssr_on > ssr_output || ssr_output <= 0))
HAL_GPIO_WritePin(SSR_PIN, 0);
HAL_GPIO_WritePin(LED_POWER, 0);
// Every 200ms, set the SSR on unless output is 0
if(HAL_GetTick() - last_ssr_on > SSR_PERIOD)
if(set.val.control_mode == MODE_PID && HAL_GetTick() - last_ssr_on > SSR_PERIOD)
// Only support heating (ssr_output > 0) right now
// Heat or cool, if we need to
if(ssr_output > 0)
HAL_GPIO_WritePin(SSR_PIN, 1);
HAL_GPIO_WritePin(LED_POWER, 1);
last_ssr_on = HAL_GetTick();
// Make sure everything is off
// Thermostatic control
if(set.val.control_mode == MODE_THERMOSTAT && HAL_GetTick() - last_thermostat > SSR_PERIOD)
// TODO: Migrate this FxP conversion to the readtemp code or similar
int8_t temp_frac = status.temp_frac > 9 ? status.temp_frac / 10 : status.temp_frac;
temp_frac = status.temp > 0 ? temp_frac : temp_frac * -1;
int32_t temp = (status.temp * 10) + temp_frac;
uint8_t plant_on = 0;
// EMZ FIXME: This could be way simpler
if(set.val.plant_type == PLANT_HEATER && status.setpoint * 10 < temp)
plant_on = 1;
else if(set.val.plant_type == PLANT_COOLER && status.setpoint * 10 > temp)
// EMZ: TODO: Refactor to output_enabled or something
if(status.pid_enabled && plant_on)
// EMZ TODO: functionalize this
last_thermostat = HAL_GetTick();
// Transmit temperature over USB-CDC on a regular basis
if(HAL_GetTick() - last_vcp_tx > VCP_TX_FREQ)
// Print temp to cdc
char tempstr[16];
itoa_fp(status.temp, status.temp_frac, tempstr);
uint8_t numlen = strlen(tempstr);
tempstr[numlen] = '\r';
tempstr[numlen+1] = '\n';
// if(set.val.usb_plugged)
// CDC_Transmit_FS(tempstr, numlen+2);
@@ -18,53 +18,67 @@ typedef union
struct {
uint32_t boottobrew;
uint32_t temp_units;
uint32_t windup_guard;
uint32_t k_p;
uint32_t k_i;
uint32_t k_d;
int32_t temp_offset;
uint32_t ignore_error;
int32_t setpoint_brew;
int32_t setpoint_steam;
uint32_t control_mode;
uint32_t plant_type;
} val;
uint16_t data[128];
} therm_settings_t;
enum tempunits {
TEMP_UNITS_CELSIUS = 0,
TEMP_UNITS_FAHRENHEIT,
};
enum state {
STATE_IDLE = 0,
STATE_SETMODE,
STATE_SETPLANTTYPE,
STATE_SETP,
STATE_SETI,
STATE_SETD,
STATE_SETSTEPS,
STATE_SETWINDUP,
STATE_SETBOOTTOBREW,
STATE_SETUNITS,
STATE_SETTEMPOFFSET,
STATE_PREHEAT,
STATE_MAINTAIN,
STATE_TC_ERROR,
STATE_RESET,
enum control_mode {
MODE_PID = 0,
MODE_THERMOSTAT,
enum plant_type {
PLANT_HEATER = 0,
PLANT_COOLER,
enum GOTO_MODE {
MODE_BOOTLOADER,
MODE_HEAT,
MODE_SETUP,
MODE_RESET,
MODE_SIZE,
enum RESET_MODE {
RESET_REBOOT = 0,
Status change: