# STM32F0xx Makefile
# #####################################
#
# Part of the uCtools project
# uctools.github.com
#######################################
# user configuration:
# SOURCES: list of sources in the user application
SOURCES = main.c system/usbd_conf.c system/usbd_cdc_if.c system/usb_device.c system/usbd_desc.c system/interrupts.c system/system_stm32f0xx.c gpio.c spi.c ssd1306.c stringhelpers.c display.c system/syslib.c storage.c flash.c max31855.c max31865.c
SOURCES = main.c system/usbd_conf.c system/usbd_cdc_if.c system/usb_device.c system/usbd_desc.c system/interrupts.c system/system_stm32f0xx.c gpio.c spi.c ssd1306.c stringhelpers.c display.c system/syslib.c storage.c flash.c max31855.c max31865.c pid.c
#SRC = $(shell find . -name *.c)
# TARGET: name of the user application
TARGET = main
# BUILD_DIR: directory to place output files in
BUILD_DIR = build
# LD_SCRIPT: location of the linker script
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_LDFLAGS: user LD flags
USER_LDFLAGS = -fno-exceptions -ffunction-sections -fno-exceptions -fdata-sections -Wl,--gc-sections
#include "stm32f0xx_hal.h"
#include "config.h"
#include "syslib.h"
#include "pid.h"
#include "states.h"
#include "ssd1306.h"
#include "max31855.h"
#include "gpio.h"
#include "spi.h"
#include "flash.h"
#include "stringhelpers.h"
#include "display.h"
#include "storage.h"
#include "usb_device.h"
#include "usbd_cdc_if.h"
// Prototypes
void process();
therm_settings_t set;
therm_status_t status;
// Globalish setting vars
static __IO uint32_t TimingDelay;
int main(void)
{
// Initialize HAL
hal_init();
// Configure the system clock
systemclock_init();
// Unset bootloader option bytes (if set)
void bootloader_unset(void);
// Init GPIO
gpio_init();
// Init USB (TODO: Handle plugged/unplugged with external power)
MX_USB_DEVICE_Init();
// set.val.usb_plugged =
// USB startup delay
HAL_Delay(1000);
HAL_GPIO_WritePin(LED_POWER, 1);
// Enter into bootloader if up button pressed on boot
if(!HAL_GPIO_ReadPin(SW_UP))
@@ -74,174 +72,111 @@ int main(void)
status.temp_frac = 0;
status.state_resume = 0;
status.state = STATE_IDLE;
status.setpoint = 0;
status.pid_enabled = 0;
// Load settings (if any) from EEPROM
restore_settings(&set);
// Go to brew instead of idle if configured thusly
if(set.val.boottobrew)
status.state = STATE_PREHEAT_BREW;
// Startup screen
ssd1306_DrawString("therm v0.2", 1, 40);
ssd1306_DrawString("protofusion.org/therm", 3, 0);
HAL_Delay(1500);
flash_restore(&set);
ssd1306_clearscreen();
// Main loop
while(1)
// Process sensor inputs
process();
// Run state machine
display_process(&set, &status);
}
// PID implementation
// TODO: Make struct that has the last_temp and i_state in it, pass by ref. Make struct that has other input values maybe.
int16_t last_pid_temp = 0;
uint8_t last_pid_temp_frac = 0;
int32_t i_state = 0;
int16_t update_pid(uint16_t k_p, uint16_t k_i, uint16_t k_d, int16_t temp, uint8_t temp_frac, int16_t setpoint)
// Calculate instantaneous error
int16_t error = setpoint - temp; // TODO: Use fixed point fraction
// Proportional component
int32_t p_term = k_p * error;
// Error accumulator (integrator)
i_state += error;
// to prevent the iTerm getting huge from lots of
// error, we use a "windup guard"
// (this happens when the machine is first turned on and
// it cant help be cold despite its best efforts)
// not necessary, but this makes windup guard values
// relative to the current iGain
int32_t windup_guard_res = set.val.windup_guard / k_i;
// Calculate integral term with windup guard
if (i_state > windup_guard_res)
i_state = windup_guard_res;
else if (i_state < -windup_guard_res)
i_state = -windup_guard_res;
int32_t i_term = k_i * i_state;
// Calculate differential term (slope since last iteration)
int32_t d_term = (k_d * (status.temp - last_pid_temp));
// Save temperature for next iteration
last_pid_temp = status.temp;
last_pid_temp_frac = status.temp_frac;
int16_t result = p_term + i_term - d_term;
// Put out tenths of percent, 0-1000.
if(result > 1000)
result = 1000;
else if(result < -1000)
result = -1000;
// Return feedback
return result;
// Soft timers
uint32_t last_ssr_on = 0;
uint32_t last_vcp_tx = 0;
uint32_t last_led = 0;
uint32_t last_pid = 0;
int16_t ssr_output = 0; // Duty cycle of ssr, 0 to SSR_PERIOD
// Turn SSR output on/off according to set duty cycle.
// TODO: Eventually maybe replace with a very slow timer or something. Double-check this code...
void process()
uint32_t ticks = HAL_GetTick();
if(ticks - last_led > 400)
if(HAL_GetTick() - last_led > 400)
last_led = ticks;
last_led = HAL_GetTick();
if((ticks - last_pid > PID_PERIOD))
if((HAL_GetTick() - last_pid > PID_PERIOD))
#ifdef MAX31855_TC_SENSOR
max31855_readtemp(spi_get(), &set, &status); // Read MAX31855
#endif
#ifdef MAX31865_RTD_SENSOR
max31865_readtemp(&set, &status);
HAL_GPIO_TogglePin(LED_POWER);
if(status.pid_enabled)
// Get ssr output for next time
int16_t power_percent = update_pid(set.val.k_p, set.val.k_i, set.val.k_d, status.temp, status.temp_frac, status.setpoint);
int16_t power_percent = pid_update(set.val.k_p, set.val.k_i, set.val.k_d, status.temp, status.temp_frac, status.setpoint, &set, &status);
//power-percent is 0-1000
ssr_output = power_percent; //(((uint32_t)SSR_PERIOD * (uint32_t)10 * (uint32_t)100) * power_percent) / (uint32_t)1000000;
else
ssr_output = 0;
last_pid = ticks;
last_pid = HAL_GetTick();
// Every 200ms, set the SSR on unless output is 0
if((ticks - last_ssr_on > SSR_PERIOD))
if(HAL_GetTick() - last_ssr_on > SSR_PERIOD)
// Only support heating (ssr_output > 0) right now
if(ssr_output > 0) {
char tempstr[6];
itoa(ssr_output, tempstr, 10);
ssd1306_DrawString(tempstr, 0, 90);
HAL_GPIO_WritePin(SSR_PIN, 1);
last_ssr_on = ticks;
last_ssr_on = HAL_GetTick();
// Kill SSR after elapsed period less than SSR_PERIOD
if(ticks - last_ssr_on > ssr_output || ssr_output == 0)
if(HAL_GetTick() - last_ssr_on > ssr_output || ssr_output == 0)
HAL_GPIO_WritePin(SSR_PIN, 0);
if(ticks - last_vcp_tx > VCP_TX_FREQ)
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);
// while(CDC_Transmit_FS("\r\n", 2) == USBD_BUSY);
last_vcp_tx = ticks;
last_vcp_tx = HAL_GetTick();
// vim:softtabstop=4 shiftwidth=4 expandtab
Status change: