TARGET:=therm

TOOLCHAIN_PATH:=/usr/bin

TOOLCHAIN_PREFIX:=arm-none-eabi

OPTLVL:=3 # Optimization level, can be [0, 1, 2, 3, s].

#PROJECT_NAME:=$(notdir $(lastword $(CURDIR)))

TOP:=$(shell readlink -f "../..")

DISCOVERY:=Utilities/STM32L100C-Discovery

STMLIB:=libraries

OLEDDRV:=oleddrv

USBDRV:=USB

STD_PERIPH:=$(STMLIB)/STM32L1xx_StdPeriph_Driver

STARTUP:=$(STMLIB)/CMSIS/Device/ST/STM32L1xx/Source/Templates/gcc_ride7

LINKER_SCRIPT:=$(CURDIR)/stm32-flash.ld

#LINKER_SCRIPT:=$(CURDIR)/../stm32_flash.ld

INCLUDE=-I$(CURDIR)

INCLUDE+=-I$(STMLIB)/CMSIS/Include

INCLUDE+=-I$(STMLIB)/CMSIS/Device/ST/STM32L1xx/Include

INCLUDE+=-I$(STD_PERIPH)/inc

INCLUDE+=-I$(DISCOVERY)

INCLUDE+=-I$(STMLIB)/$(OLEDDRV)

INCLUDE+=-I$(STMLIB)/$(USBDRV)

# vpath is used so object files are written to the current directory instead

# of the same directory as their source files

vpath %.c $(DISCOVERY) $(STD_PERIPH)/src \

          $(STMLIB)/USB \

          $(STMLIB)/STM32_USB-FS_Device_Library/Class/hid/src \

          $(STMLIB)/STM32_USB-FS_Device_Library/Core/src

vpath %.s $(STARTUP)

ASRC=startup_stm32l1xx_mdp.s

# Project Source Files

SRC=main.c

SRC+=stm32l1xx_it.c

SRC+=system_stm32l1xx.c

SRC+=stm32l100c_discovery.c

SRC+=ssd1306.c

SRC+=eeprom_min.c

SRC+=gpio.c

SRC+=spi.c

SRC+=stringhelpers.c

# Discovery Source Files

#SRC+=stm32f4_discovery_lis302dl.c

#SRC+=stm32f4_discovery.c

#SRC+=stm32f4_discovery_audio_codec.c

# Standard Peripheral Source Files

SRC+=stm32l1xx_syscfg.c

SRC+=misc.c

SRC+=stm32l1xx_adc.c

SRC+=stm32l1xx_dac.c

SRC+=stm32l1xx_dma.c

SRC+=stm32l1xx_exti.c

SRC+=stm32l1xx_flash.c

SRC+=stm32l1xx_gpio.c

SRC+=stm32l1xx_i2c.c

SRC+=stm32l1xx_rcc.c

SRC+=stm32l1xx_spi.c

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

all: $(OBJ)

	$(CC) -o $(TARGET).elf $(LDFLAGS) $(OBJ)	$(LDLIBS)

	$(OBJCOPY) -O ihex   $(TARGET).elf $(TARGET).hex

	$(OBJCOPY) -O binary $(TARGET).elf $(TARGET).bin

.PHONY: clean

clean:

	rm -f $(OBJ)

	rm -f $(TARGET).elf

	rm -f $(TARGET).hex

	rm -f $(TARGET).bin

# Display size

size: $(TARGET).elf

	@echo Invoking: ARM GNU Print Size

	$(SIZE) --format=berkeley $<

	@echo

    STATE_IDLE = 0,

    STATE_SETP,

    STATE_SETI,

    STATE_SETD,

    STATE_SETSTEPS,

    STATE_SETWINDUP,

    STATE_SETBOOTTOBREW,

    STATE_SETUNITS,

    STATE_PREHEAT_BREW,

    STATE_MAINTAIN_BREW,

    STATE_PREHEAT_STEAM,

    STATE_MAINTAIN_STEAM,

    STATE_TC_ERROR

};

uint8_t state = STATE_IDLE;

static __IO uint32_t TimingDelay;

// Move to header file

void process();

void machine();

void restore_settings();

void save_settings();

void save_setpoints();

int main(void)

{

    // Init clocks

    SystemInit();

    // Init GPIO

    init_gpio();

    // Turn on power LED

    GPIO_SetBits(LED_POWER);

    // TODO: Awesome pwm of power LED (TIM4_CH4 or TIM11_CH1)

    // Configure 1ms SysTick (change if more temporal resolution needed) 

    RCC_ClocksTypeDef RCC_Clocks;

    RCC_GetClocksFreq(&RCC_Clocks);

    SysTick_Config(RCC_Clocks.HCLK_Frequency / 1000);

    // Init SPI busses

    init_spi();

    // Init OLED over SPI

    ssd1306_Init();

    ssd1306_clearscreen();

    // Check for problems on startup

    if(clock_fail) {

        //ssd1306_DrawStringBig("ERROR: Check Xtal", 2, 0);

        ssd1306_DrawStringBig("NO XTAL", 2, 0);

        delay(1000);

        ssd1306_clearscreen();

    }

    // Init USB

    //Set_System(); // hw_config.h

    Set_USBClock();

    USB_Interrupts_Config();

    USB_Init();

    //SYSCFG_USBPuCmd(ENABLE);

    //PowerOn();

    // Startup screen 

    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)

  i_state += error;

  // to prevent the iTerm getting huge despite 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

  int16_t windup_guard_res = 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;

  int16_t i_term = k_i * i_state;

  // Calculate differential term (slope since last iteration)

  int16_t d_term = (k_d * (temp - last_pid_temp));

  // Save temperature for next iteration

  last_pid_temp = temp;

  last_pid_temp_frac = 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;

}

uint32_t last_ssr_on = 0;

uint32_t last_led = 0;

int32_t setpoint = 0;

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