#include "stm32f0xx_hal.h"
#include "ssd1306.h"
#include "stringhelpers.h"
#include "display.h"
#include "config.h"
#include "states.h"
#include "syslib.h"
#include "flash.h"
#include "gpio.h"
static uint8_t goto_mode = 2;
// Private function prototypes
static void draw_setpoint(therm_status_t* status);
// State machine
// Button transition variables
static uint8_t sw_btn_last = 0;
static uint8_t sw_up_last = 0;
static uint8_t sw_down_last = 0;
static uint8_t sw_left_last = 0;
static uint8_t sw_right_last = 0;
// Buttonpress macros
#define SW_BTN_PRESSED (sw_btn_last == 0 && sw_btn == 1) // rising edge on buttonpress
#define SW_UP_PRESSED (sw_up_last == 0 && sw_up == 1)
#define SW_DOWN_PRESSED (sw_down_last == 0 && sw_down == 1)
#define SW_LEFT_PRESSED (sw_left_last == 0 && sw_left == 1)
#define SW_RIGHT_PRESSED (sw_right_last == 0 && sw_right == 1)
// States
static uint8_t trigger_drawsetpoint = 1;
static int16_t last_temp = 21245;
// Display state machine
void display_process(therm_settings_t* set, therm_status_t* status)
{
uint8_t last_state = status->state;
uint8_t temp_changed = status->temp != last_temp;
last_temp = status->temp;
uint8_t sw_btn = !HAL_GPIO_ReadPin(SW_BTN);
uint8_t sw_up = !HAL_GPIO_ReadPin(SW_UP);
uint8_t sw_down = !HAL_GPIO_ReadPin(SW_DOWN);
uint8_t sw_left = !HAL_GPIO_ReadPin(SW_LEFT);
uint8_t sw_right = !HAL_GPIO_ReadPin(SW_RIGHT);
switch(status->state)
// Idle state
case STATE_IDLE:
// Write text to OLED
// [ therm :: idle ]
ssd1306_drawstring("therm :: idle ", 0, 40);
status->pid_enabled = 0;
if(temp_changed) {
char tempstr[6];
itoa_fp(status->temp, status->temp_frac, tempstr);
ssd1306_drawstring("Temp: ", 3, 40);
ssd1306_drawstring(" ", 3, 72);
ssd1306_drawstring(tempstr, 3, 72);
}
ssd1306_drawlogo();
switch(goto_mode) {
case 3:
ssd1306_drawstring("-> loader ", 1, 40);
} break;
case 2:
ssd1306_drawstring("-> heat ", 1, 40);
case 1:
ssd1306_drawstring("-> setup ", 1, 40);
case 0:
ssd1306_drawstring("-> reset ", 1, 40);
// Button handler
if(SW_BTN_PRESSED) {
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
status->state = STATE_IDLE; // Just in case
status->state = STATE_PREHEAT_BREW;
status->state = STATE_PREHEAT;
break;
status->state = STATE_SETP;
status->state = STATE_IDLE;
//flash_erase();
NVIC_SystemReset();
default:
else if(SW_UP_PRESSED && goto_mode < 3) {
goto_mode++;
else if(SW_DOWN_PRESSED && goto_mode > 0) {
goto_mode--;
// Event Handler
// N/A
case STATE_SETP:
// [ therm :: set p ]
// [ p = 12 ]
ssd1306_drawstring("Proportional", 0, 40);
itoa(set->val.k_p, tempstr, 10);
ssd1306_drawstring("P=", 1, 45);
ssd1306_drawstring(" ", 1, 57);
ssd1306_drawstring(tempstr, 1, 57);
ssd1306_drawstring("Press to accept", 3, 40);
status->state = STATE_SETI;
else {
user_input(&set->val.k_p);
case STATE_SETI:
// [ therm :: set i ]
// [ i = 12 ]
ssd1306_drawstring("Integral", 0, 40);
itoa(set->val.k_i, tempstr, 10);
ssd1306_drawstring("I=", 1, 45);
status->state = STATE_SETD;
user_input(&set->val.k_i);
case STATE_SETD:
// [ therm :: set d ]
// [ d = 12 ]
ssd1306_drawstring("Derivative", 0, 40);
itoa(set->val.k_d, tempstr, 10);
ssd1306_drawstring("D=", 1, 45);
status->state = STATE_SETWINDUP;
user_input(&set->val.k_d);
case STATE_SETWINDUP:
// [ therm :: set windup ]
// [ g = 12 ]
ssd1306_drawstring("Windup Guard", 0, 40);
itoa(set->val.windup_guard, tempstr, 10);
ssd1306_drawstring("G=", 1, 45);
status->state = STATE_SETBOOTTOBREW;
user_input(&set->val.windup_guard);
case STATE_SETBOOTTOBREW:
ssd1306_drawstring("Start on Boot", 0, 40);
ssd1306_drawstring("sob=", 1, 45);
if(set->val.boottobrew)
ssd1306_drawstring("Enabled ", 1, 70);
else
ssd1306_drawstring("Disabled", 1, 70);
status->state = STATE_SETUNITS;
else if(!HAL_GPIO_ReadPin(SW_UP)) {
set->val.boottobrew = 1;
else if(!HAL_GPIO_ReadPin(SW_DOWN)) {
set->val.boottobrew = 0;
case STATE_SETUNITS:
ssd1306_drawstring("Units: ", 0, 40);
if(set->val.temp_units == TEMP_UNITS_FAHRENHEIT)
ssd1306_drawstring("Fahrenheit", 1, 60);
ssd1306_drawstring("Celsius ", 1, 60);
status->state = STATE_SETTEMPOFFSET;
set->val.temp_units = TEMP_UNITS_FAHRENHEIT;
set->val.temp_units = TEMP_UNITS_CELSIUS;
case STATE_SETTEMPOFFSET:
// [ therm :: set temp offset ]
ssd1306_drawstring("Temp Cal Offset", 0, 40);
itoa(set->val.temp_offset, tempstr, 10);
ssd1306_drawstring("O=", 1, 45);
flash_save(&set);
user_input_signed(&set->val.temp_offset);
case STATE_PREHEAT_BREW:
case STATE_PREHEAT:
// [ therm : preheating brew ]
// [ 30 => 120 C ]
ssd1306_drawstring("Preheating...", 0, 0);
//ssd1306_drawlogo();
draw_setpoint(status);
status->pid_enabled = 1;
status->setpoint = set->val.setpoint_brew;
user_input(&set->val.setpoint_brew);
if(status->temp >= status->setpoint) {
status->state = STATE_MAINTAIN_BREW;
status->state = STATE_MAINTAIN;
case STATE_MAINTAIN_BREW:
case STATE_MAINTAIN:
// [ therm : ready to brew ]
ssd1306_drawstring("Preheated!", 0, 0);
case STATE_PREHEAT_STEAM:
// [ therm : preheating steam ]
status->setpoint = set->val.setpoint_steam;
user_input(&set->val.setpoint_steam);
status->state = STATE_MAINTAIN_STEAM;
case STATE_MAINTAIN_STEAM:
// [ therm : ready to steam ]
ssd1306_drawstring("Ready to Steam!", 0, 0);
// Thermocouple error
case STATE_TC_ERROR:
ssd1306_drawstring("Error: ", 0, 0);
itoa(status->tc_errno, tempstr, 10);
ssd1306_drawstring(tempstr, 0, 57);
if(status->tc_errno == 1)
ssd1306_drawstring(" TC Open Circuit", 1, 0);
else if(status->tc_errno == 4)
ssd1306_drawstring(" TC Short to GND", 1, 0);
else if(status->tc_errno == 8)
ssd1306_drawstring(" TC Short to VCC", 1, 0);
ssd1306_drawstring("#?, Unknown Error", 1, 0);
ssd1306_drawstring(" ", 2, 0);
ssd1306_drawstring("-> to ignore all or", 2, 0);
ssd1306_drawstring("press to continue", 3, 0);
else if(SW_RIGHT_PRESSED) {
set->val.ignore_tc_error = 1;
// Maybe handle if TC is plugged in
// Something is terribly wrong
if(last_state != status->state) {
// Clear screen on state change
goto_mode = 2;
trigger_drawsetpoint = 1;
// Last buttonpress
sw_btn_last = sw_btn;
sw_up_last = sw_up;
sw_down_last = sw_down;
sw_left_last = sw_left;
sw_right_last = sw_right;
static int32_t temp_last = 43002;
static int32_t setpoint_last = 10023;
void draw_setpoint(therm_status_t* status) {
// Draw current setpoint on display
static void draw_setpoint(therm_status_t* status) {
// FIXME: need to do this when switching modes too
if(status->temp != temp_last || trigger_drawsetpoint) {
char tempstr[3];
ssd1306_drawstringbig(" ", 3, 0);
ssd1306_drawstringbig(tempstr, 3, 0);
if(trigger_drawsetpoint)
ssd1306_drawstringbig(">", 3, 74);
if(status->setpoint != setpoint_last || trigger_drawsetpoint) {
itoa(status->setpoint, tempstr, 10);
ssd1306_drawstringbig(" ", 3, 90);
ssd1306_drawstringbig(tempstr, 3, 90);
trigger_drawsetpoint = 0;
setpoint_last = status->setpoint;
temp_last = status->temp;
// vim:softtabstop=4 shiftwidth=4 expandtab
#ifndef DISPLAY_H
#define DISPLAY_H
void display_process(therm_settings_t* set, therm_status_t* status);
void draw_setpoint(therm_status_t* status);
#endif
#include "pid.h"
#include "max31855.h"
#include "spi.h"
#include "usb_device.h"
#include "usbd_cdc_if.h"
therm_settings_t set;
therm_status_t status;
int main(void)
// Initialize HAL
hal_init();
// Configure the system clock
systemclock_init();
// Unset bootloader option bytes (if set)
// FIXME this was never getting called. Try again sometime.
//bootloader_unset();
// 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(500);
HAL_GPIO_WritePin(LED_POWER, 1);
// Enter into bootloader if up button pressed on boot
if(!HAL_GPIO_ReadPin(SW_UP))
bootloader_enter();
// Init SPI busses
spi_init();
// Init OLED over SPI
ssd1306_init();
// Default settings
set.val.boottobrew = 0;
set.val.temp_units = TEMP_UNITS_FAHRENHEIT;
set.val.windup_guard = 200;
set.val.k_p = 10;
set.val.k_i = 10;
set.val.k_d = 1;
set.val.ignore_tc_error = 0;
set.val.setpoint_brew = 70;
set.val.setpoint_steam = 70;
// Default status
status.temp = 0;
status.temp_frac = 0;
status.state_resume = 0;
status.state = STATE_IDLE;
status.setpoint = 70;
status.pid_enabled = 0;
// Go to brew instead of idle if configured thusly
if(set.val.boottobrew)
status.state = STATE_PREHEAT_BREW;
status.state = STATE_PREHEAT;
// Startup screen
ssd1306_drawstring("therm v0.2", 1, 40);
ssd1306_drawstring("protofusion.org/therm", 3, 0);
HAL_Delay(1000);
// Restore settings from flash memory
flash_restore(&set);
// 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
// Main loop
while(1)
// Process sensor inputs
if(HAL_GetTick() - last_led > 400)
last_led = HAL_GetTick();
if((HAL_GetTick() - last_pid > PID_PERIOD))
#ifdef MAX31855_TC_SENSOR
max31855_readtemp(spi_get(), &set, &status); // Read MAX31855
#ifdef MAX31865_RTD_SENSOR
max31865_readtemp(&set, &status);
if(status.pid_enabled)
// Get ssr output for next time
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;
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)
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)
// Only support heating (ssr_output > 0) right now
if(ssr_output > 0)
itoa(ssr_output, tempstr, 10);
ssd1306_drawstring(tempstr, 0, 90);
HAL_GPIO_WritePin(SSR_PIN, 1);
last_ssr_on = HAL_GetTick();
// Make sure everything is off
// Transmit temperature over USB-CDC on a regulat 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);
// while(CDC_Transmit_FS("\r\n", 2) == USBD_BUSY);
last_vcp_tx = HAL_GetTick();
// Run state machine
display_process(&set, &status);
#ifndef STATES_H
#define STATES_H
typedef struct {
int32_t temp;
uint8_t temp_frac;
uint8_t state_resume;
uint8_t state;
int32_t setpoint;
uint8_t pid_enabled;
uint8_t tc_errno;
} therm_status_t;
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_tc_error;
int32_t setpoint_brew;
int32_t setpoint_steam;
} val;
uint16_t data[128];
} therm_settings_t;
enum tempunits {
TEMP_UNITS_CELSIUS = 0,
TEMP_UNITS_FAHRENHEIT,
};
enum state {
STATE_IDLE = 0,
STATE_SETP,
STATE_SETI,
STATE_SETD,
STATE_SETSTEPS,
STATE_SETWINDUP,
STATE_SETBOOTTOBREW,
STATE_SETUNITS,
STATE_SETTEMPOFFSET,
STATE_PREHEAT_BREW,
STATE_MAINTAIN_BREW,
STATE_PREHEAT_STEAM,
STATE_MAINTAIN_STEAM,
STATE_PREHEAT,
STATE_MAINTAIN,
STATE_TC_ERROR
STATE_TC_ERROR,
Status change: