@@ -19,24 +19,25 @@ extern __IO uint32_t Receive_length ;
extern __IO uint32_t length ;
uint8_t Send_Buffer[64];
uint32_t packet_sent=1;
uint32_t packet_receive=1;
// State definition
enum state {
STATE_IDLE = 0,
STATE_SETP,
STATE_SETI,
STATE_SETD,
STATE_SETWINDUP,
STATE_PREHEAT_BREW,
STATE_MAINTAIN_BREW,
STATE_PREHEAT_STEAM,
STATE_MAINTAIN_STEAM,
};
static __IO uint32_t TimingDelay;
// Move to header file
void init_gpio();
@@ -193,47 +194,55 @@ int16_t update_pid(uint16_t k_p, uint16_
}
uint32_t ticks = 0;
uint32_t last_ssr_on = 0;
uint32_t last_led = 0;
int32_t setpoint = 0;
uint16_t k_p = 1;
uint16_t k_i = 1;
uint16_t k_d = 1;
uint16_t windup_guard = 1;
int16_t ssr_output = 0; // Duty cycle of ssr, 0 to SSR_PERIOD
uint8_t pid_enabled = 0;
// Process things
void process()
{
update_temp(); // Read MAX31855
// TODO: Add calibration offset (linear)
if(ticks - last_led > 400)
GPIO_ToggleBits(LED_POWER);
last_led = ticks;
// Every 200ms, set the SSR on unless output is 0
if((ticks - last_ssr_on > SSR_PERIOD))
if(pid_enabled)
// Get ssr output for next time
int16_t power_percent = update_pid(k_p, k_i, k_d, temp, temp_frac, setpoint);
//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;
// Only support heating (ssr_output > 0) right now
if(ssr_output > 0) {
char tempstr[6];
itoa(ssr_output, tempstr);
ssd1306_DrawString("#=", 2, 45);
ssd1306_DrawString(" ", 2, 57);
ssd1306_DrawString(tempstr, 2, 57);
GPIO_SetBits(LED_STAT);
last_ssr_on = ticks;
@@ -283,61 +292,62 @@ void machine()
uint8_t sw_down = !GPIO_ReadInputDataBit(SW_DOWN);
uint8_t sw_left = !GPIO_ReadInputDataBit(SW_LEFT);
uint8_t sw_right = !GPIO_ReadInputDataBit(SW_RIGHT);
switch(state)
// Idle state
case STATE_IDLE:
// Write text to OLED
// [ therm :: idle ]
ssd1306_DrawString("therm :: idle ", 0, 40);
pid_enabled = 0;
itoa_fp(temp, temp_frac, tempstr);
ssd1306_DrawString("Temp: ", 3, 40);
ssd1306_DrawString(" ", 3, 70);
ssd1306_DrawString(" ", 3, 72);
ssd1306_DrawString(tempstr, 3, 72);
ssd1306_drawlogo();
switch(goto_mode) {
case 2:
ssd1306_DrawString("-> brew ", 1, 40);
} break;
case 1:
ssd1306_DrawString("-> set P/I/D", 1, 40);
ssd1306_DrawString("-> setup ", 1, 40);
case 0:
ssd1306_DrawString("-> reset ", 1, 40);
// Button handler
if(SW_BTN_PRESSED) {
state = STATE_PREHEAT_BREW;
break;
state = STATE_SETP;
state = STATE_IDLE;
default:
else if(SW_UP_PRESSED && goto_mode < 2) {
goto_mode++;
else if(SW_DOWN_PRESSED && k_p > 0 && goto_mode > 0) {
goto_mode--;
@@ -421,46 +431,82 @@ void machine()
itoa(k_d, tempstr);
ssd1306_DrawString("D=", 1, 45);
ssd1306_DrawString(" ", 1, 57);
ssd1306_DrawString(tempstr, 1, 57);
ssd1306_DrawString("Press to accept", 3, 40);
state = STATE_SETWINDUP;
else if(!GPIO_ReadInputDataBit(SW_UP)) {
k_d++;
else if(!GPIO_ReadInputDataBit(SW_DOWN) && k_d > 0) {
k_d--;
// Event Handler
// N/A
case STATE_SETWINDUP:
// [ therm :: set windup ]
// [ g = 12 ]
ssd1306_DrawString("Windup Guard", 0, 40);
itoa(windup_guard, tempstr);
ssd1306_DrawString("G=", 1, 45);
windup_guard++;
else if(!GPIO_ReadInputDataBit(SW_DOWN) && windup_guard > 0) {
windup_guard--;
case STATE_PREHEAT_BREW:
// [ therm : preheating brew ]
// [ 30 => 120 C ]
ssd1306_DrawString("Preheating...", 0, 40);
draw_setpoint();
pid_enabled = 1;
setpoint++;
else if(!GPIO_ReadInputDataBit(SW_DOWN) && setpoint > 0) {
setpoint--;
@@ -471,24 +517,25 @@ void machine()
case STATE_MAINTAIN_BREW:
// [ therm : ready to brew ]
ssd1306_DrawString("Ready to Brew!", 0, 40);
@@ -497,24 +544,25 @@ void machine()
case STATE_PREHEAT_STEAM:
// [ therm : preheating steam ]
@@ -525,46 +573,48 @@ void machine()
case STATE_MAINTAIN_STEAM:
// [ therm : ready to steam ]
ssd1306_DrawString("Ready to Steam!", 0, 40);
// Something is terribly wrong
if(last_state != state) {
// Clear screen on state change
ssd1306_clearscreen();
sw_btn_last = sw_btn;
sw_up_last = sw_up;
sw_down_last = sw_down;
Status change: