SRC+=stm32l1xx_tim.c

# USB Source Files

SRC+=usb_core.c

SRC+=usb_init.c

SRC+=usb_int.c

SRC+=usb_mem.c

SRC+=usb_regs.c

SRC+=usb_sil.c

SRC+=hw_config.c

SRC+=usb_desc.c

SRC+=usb_endp.c

SRC+=usb_istr.c

SRC+=usb_prop.c

SRC+=usb_pwr.c

CDEFS=-DUSE_STDPERIPH_DRIVER

CDEFS+=-DSTM32L1XX

CDEFS+=-DMANGUSTA_DISCOVERY

#CDEFS+=-DUSE_USB_OTG_FS

CDEFS+=-DHSE_VALUE=8000000

#EMZ Optimized: 

# Default:  MCUFLAGS=-mcpu=cortex-m3 -mthumb -ffunction-sections -fdata-sections

#MCUFLAGS=-mcpu=cortex-m4 -mthumb -mlittle-endian -mfpu=fpa -mfloat-abi=hard -mthumb-interwork

#MCUFLAGS=-mcpu=cortex-m4 -mfpu=vfpv4-sp-d16 -mfloat-abi=hard

COMMONFLAGS=-O$(OPTLVL) -g -Wall

CFLAGS=$(COMMONFLAGS) $(MCUFLAGS) $(INCLUDE) $(CDEFS)

LDLIBS=

LDFLAGS=$(COMMONFLAGS) -fno-exceptions -ffunction-sections -fdata-sections \

        -nostartfiles -Wl,--gc-sections,-T$(LINKER_SCRIPT)

#####

#####

OBJ = $(SRC:%.c=%.o) $(ASRC:%.s=%.o)

CC=$(TOOLCHAIN_PATH)/$(TOOLCHAIN_PREFIX)-gcc

LD=$(TOOLCHAIN_PATH)/$(TOOLCHAIN_PREFIX)-gcc

OBJCOPY=$(TOOLCHAIN_PATH)/$(TOOLCHAIN_PREFIX)-objcopy

AS=$(TOOLCHAIN_PATH)/$(TOOLCHAIN_PREFIX)-as

AR=$(TOOLCHAIN_PATH)/$(TOOLCHAIN_PREFIX)-ar

GDB=$(TOOLCHAIN_PATH)/$(TOOLCHAIN_PREFIX)-gdb

SIZE=$(TOOLCHAIN_PATH)/$(TOOLCHAIN_PREFIX)-size

    ssd1306_DrawString("therm v0.1", 1, 40);

    ssd1306_DrawString("protofusion.org/therm", 3, 0);

    delay(1500);

    ssd1306_clearscreen();

    restore_settings();

    if(boottobrew)

      state = STATE_PREHEAT_BREW; // Go to brew instead of idle if configured thusly

    GPIO_ResetBits(LED_STAT);

    // Main loop

    while(1)

    {

        // Process sensor inputs

        process();

        // Run state machine

        machine(); 

    }

}

// Read temperature and update global temp vars

uint8_t temp_frac = 0;

void update_temp() {

    // Assert CS

    GPIO_ResetBits(MAX_CS);

    delay(1);

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

    SPI_I2S_SendData(SPI2, 0xAAAA); // send dummy data

    //SPI_I2S_SendData(SPI2, 0xAA); // send dummy data

    uint16_t temp_pre = SPI_I2S_ReceiveData(SPI2);

    if(temp_pre & 0b0000000000000010) {

        ssd1306_DrawString("Fatal Error", 3, 35);

        state = STATE_TC_ERROR;

    }

    else if(temp_pre & 0b0000000000000001 && !ignore_tc_error) {

        state = STATE_TC_ERROR;

        temp = 0;

        temp_frac = 0;

    }

    else 

    {

        uint8_t sign = temp >> 15;// top bit is sign

        temp_pre = temp_pre >> 2; // Drop 2 lowest bits

        temp_frac = temp_pre & 0b11; // get fractional part

        temp_frac *= 25; // each bit is .25 a degree, up to fixed point

        temp_pre = temp_pre >> 2; // Drop 2 fractional bits 

        if(sign) {

            temp = -temp_pre;

        }

        else {

            temp = temp_pre;

        }

        if(temp_units == TEMP_UNITS_FAHRENHEIT) {

            temp += 32;

        }

    }

    // Deassert CS

    delay(1);

    GPIO_SetBits(MAX_CS);

}

// 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;

int16_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 = (int16_t)setpoint - (int16_t)temp; // TODO: Use fixed point fraction

  // Proportional component

  int16_t p_term = k_p * error;

  // Error accumulator (integrator)