#define SW_BTN  GPIOB, GPIO_Pin_3

#define SW_UP   GPIOB, GPIO_Pin_7

#define SW_DOWN GPIOB, GPIO_Pin_6

#define SW_LEFT GPIOB, GPIO_Pin_5

#define SW_RIGHT GPIOB, GPIO_Pin_4

static __IO uint32_t TimingDelay;

void init_gpio();

void init_spi();

void process();

void machine();

int main(void)

{

    // Init clocks

    SystemInit();

    init_gpio();

    Set_USBClock();

    USB_Interrupts_Config();

    GPIO_SetBits(LED_POWER);

    RCC_ClocksTypeDef RCC_Clocks;

    // SysTick end of count event each 1ms

    RCC_GetClocksFreq(&RCC_Clocks);

    SysTick_Config(RCC_Clocks.HCLK_Frequency / 1000);

    GPIO_ResetBits(LED_STAT);

    Delay(100);

    //ssd1306_Init();

    //ssd1306_DrawPoint(3,3,1);

    //ssd1306_DrawPoint(5,5,0);

    GPIO_SetBits(LED_POWER);

    Delay(500);

    GPIO_ResetBits(LED_POWER);

    init_spi();

    while(1)

   {  

        // Process sensor inputs [TODO: 5hz?]

        process();

        // Run state machine [TODO: 50hz?]

        machine(); 

        // probably just passed the actual port

        // TODO: Grab buttonpresses with interrupts

        uint8_t sw_btn = GPIO_ReadInputDataBit(SW_BTN);

        uint8_t sw_up = GPIO_ReadInputDataBit(SW_UP);

        uint8_t sw_down = GPIO_ReadInputDataBit(SW_DOWN);

        uint8_t sw_left = GPIO_ReadInputDataBit(SW_LEFT);

        uint8_t sw_right = GPIO_ReadInputDataBit(SW_RIGHT);

        SPI_I2S_SendData(SPI2,0xFA);

        SPI_I2S_SendData(SPI1,0xFA);

        if(!GPIO_ReadInputDataBit(GPIOB, GPIO_Pin_3)) {

            GPIO_ToggleBits(LED_STAT);

        }

        Delay(50);

    }

}

int32_t temp = 0;

int32_t setpoint = 0;

int32_t p = 1;

int32_t i = 1;

int32_t d = 1;

// Process things

void process()

{

    // Read MAX temp sensor

    GPIO_ResetBits(MAX_CS);

    // Assert CS

    // This may not clock at all... might need to send 16 bits first

    uint8_t retval = SPI_I2S_ReceiveData(SPI2);

    // Deassert CS

    GPIO_SetBits(MAX_CS);

    if((!retval || (temp & 0x2) != 0))

    if((temp & 0x4)!= 0)

        return; // Open thermocouple

    temp = (temp & 0x7FF8) >> 5;

    // TODO: Add calibration offset (linear)

    // Perform PID calculations

    // Write output to SSR

}

enum state {

    STATE_IDLE = 0,

    STATE_SETP,

    STATE_SETI,

    STATE_SETD,

    STATE_PREHEAT_BREW,

    STATE_MAINTAIN_BREW,

    STATE_PREHEAT_STEAM,

    STATE_MAINTAIN_STEAM,

};

uint8_t state = STATE_IDLE;

            if(temp >= setpoint) {

                state = STATE_MAINTAIN_STEAM;

            }

        } break;

        case STATE_MAINTAIN_STEAM:

        {

            // Write text to OLED

            // [ therm : ready to steam ]

            // [ 30 => 120 C            ]

            // Button handler

            if(GPIO_ReadInputDataBit(SW_BTN)) {

                state = STATE_IDLE;

            }

            // Event Handler

            // N/A

        } break;

        // Something is terribly wrong

        {

            state = STATE_IDLE;

        } break;

    }

}

/**

  * @brief  Inserts a delay time.

  * @param  nTime: specifies the delay time length, in 1 ms.

  * @retval None

  */

void Delay(__IO uint32_t nTime)

{

  TimingDelay = nTime;

  while(TimingDelay != 0);

}

/**

  * @brief  Decrements the TimingDelay variable.

  * @param  None