adc.c

/*
 * TongSheng TSDZ2 motor controller firmware/
 *
 * Copyright (C) Casainho, 2018.
 *
 * Released under the GPL License, Version 3
 */

#include <stdint.h>
#include <stdio.h>
#include "stm8s.h"
#include "pins.h"
#include "stm8s_adc1.h"
#include "adc.h"
#include "ebike_app.h"
#include "motor.h"

static void adc_trigger (void);

void adc_init (void)
{
  uint16_t ui16_counter;
  uint16_t ui16_adc_battery_current_offset;
  uint16_t ui16_adc_torque_sensor_offset;
  uint8_t ui8_i;

  //init GPIO for the used ADC pins
  GPIO_Init(GPIOB,
	    (GPIO_PIN_7 | GPIO_PIN_6 | GPIO_PIN_5 | GPIO_PIN_3),
	    GPIO_MODE_IN_FL_NO_IT);

  //init ADC1 peripheral
  ADC1_Init(ADC1_CONVERSIONMODE_SINGLE,
      ADC1_CHANNEL_7,
      ADC1_PRESSEL_FCPU_D2,
      ADC1_EXTTRIG_TIM,
      DISABLE,
      ADC1_ALIGN_LEFT,
      (ADC1_SCHMITTTRIG_CHANNEL3 | ADC1_SCHMITTTRIG_CHANNEL5 | ADC1_SCHMITTTRIG_CHANNEL6 | ADC1_SCHMITTTRIG_CHANNEL7),
            DISABLE);

  ADC1_ScanModeCmd (ENABLE);
  ADC1_Cmd (ENABLE);

  //********************************************************************************
  // next code is for "calibrating" the offset value of some ADC channels

  // read and discard few samples of ADC, to make sure the next samples are ok
  for (ui8_i = 0; ui8_i <= 64; ui8_i++)
  {
    ui16_counter = TIM3_GetCounter () + 10; // delay ~10ms
    while (TIM3_GetCounter () < ui16_counter) ; // delay ~10ms
    adc_trigger ();
    while (!ADC1_GetFlagStatus (ADC1_FLAG_EOC)) ; // wait for end of conversion
  }

  // read and average a few values of ADC battery current
  ui16_adc_battery_current_offset = 0;
  for (ui8_i = 0; ui8_i <= 16; ui8_i++)
  {
    ui16_counter = TIM3_GetCounter () + 10; // delay ~10ms
    while (TIM3_GetCounter () < ui16_counter) ; // delay ~10ms
    adc_trigger ();
    while (!ADC1_GetFlagStatus (ADC1_FLAG_EOC)) ; // wait for end of conversion
    ui16_adc_battery_current_offset += UI8_ADC_BATTERY_CURRENT;
  }
  ui16_adc_battery_current_offset >>= 4;
  ui8_adc_battery_current_offset = ui16_adc_battery_current_offset >> 2;
  ui8_adc_motor_phase_current_offset = ui8_adc_battery_current_offset;

  // read and average a few values of ADC torque sensor
  ui16_adc_torque_sensor_offset = 0;
  for (ui8_i = 0; ui8_i <= 16; ui8_i++)
  {
    ui16_counter = TIM3_GetCounter () + 10; // delay ~10ms
    while (TIM3_GetCounter () < ui16_counter) ; // delay ~10ms
    adc_trigger ();
    while (!ADC1_GetFlagStatus (ADC1_FLAG_EOC)) ; // wait for end of conversion
    ui16_adc_torque_sensor_offset += UI8_ADC_TORQUE_SENSOR;
  }
  ui16_adc_torque_sensor_offset >>= 4;

  ui8_adc_torque_sensor_min_value = ((uint8_t) ui16_adc_torque_sensor_offset) + ADC_TORQUE_SENSOR_THRESHOLD;
  ui8_adc_torque_sensor_max_value = ui8_adc_torque_sensor_min_value + 32;
}

static void adc_trigger (void)
{
  // trigger ADC conversion of all channels (scan conversion, buffered)
  ADC1->CSR &= 0x07; // clear EOC flag first (selected also channel 7)
  ADC1->CR1 |= ADC1_CR1_ADON; // Start ADC1 conversion
}

uint16_t ui16_adc_read_battery_current_10b (void)
{
  uint16_t temph;
  uint8_t templ;

  templ = *(uint8_t*)(0x53EB);
  temph = *(uint8_t*)(0x53EA);

  return ((uint16_t) temph) << 2 | ((uint16_t) templ);
}

uint16_t ui16_adc_read_torque_sensor_10b (void)
{
  uint16_t temph;
  uint8_t templ;

  templ = *(uint8_t*)(0x53E9);
  temph = *(uint8_t*)(0x53E8);

  return ((uint16_t) temph) << 2 | ((uint16_t) templ);
}

uint16_t ui16_adc_read_throttle_10b (void)
{
  uint16_t temph;
  uint8_t templ;

  templ = *(uint8_t*)(0x53EF);
  temph = *(uint8_t*)(0x53EE);

  return ((uint16_t) temph) << 2 | ((uint16_t) templ);
}

uint16_t ui16_adc_read_battery_voltage_10b (void)
{
  uint16_t temph;
  uint8_t templ;

  templ = *(uint8_t*)(0x53ED);
  temph = *(uint8_t*)(0x53EC);

  return ((uint16_t) temph) << 2 | ((uint16_t) templ);
}