BQ76952: BQ76952 I2C programming with STM32F103 microcontroller issue!

Dear Arjun,

Do you know if the device you are using supports clock stretching? If the same program is working on another MCU, it would imply that either the hardware of the non-working MCU is insufficient or the device is improperly configured. One issue could be the clock for I2C communication isn't properly configured on one of the MCUs. Is there any differences between the configurations that you set up on each device?

Best,

Asher Nederveld

Thank you for fast replay, 

Sir,  I got the solution for the same. but I am not able to read the proper data(eg. specially temperature)  from the BQ79XXX. can get the sample code for stm32 to the read the temperature sensor.

if have then please attached.

I use to taking BQ79XXX data over UART. and have getting this ?/

1304.349976 temp1
1304.349976 temp1
1304.349976 temp1
1304.349976 temp1
1304.349976 temp1
1304.349976 temp1
1304.349976 temp1
1304.349976 temp1
1304.349976 temp1
1304.349976 temp1

And sir i am used below code....

////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////

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 * --/COPYRIGHT--*//* USER CODE BEGIN Header */
/**
  ******************************************************************************
  * @file           : main.c
  * @brief          : Main program body 
  * (Non-USER sections generated from STM32CubeMX software)
  ******************************************************************************
  * @attention
  *
  * <h2><center>© Copyright (c) 2020 STMicroelectronics.
  * All rights reserved.</center></h2>
  *
  * This software component is licensed by ST under BSD 3-Clause license,
  * the "License"; You may not use this file except in compliance with the
  * License. You may obtain a copy of the License at:
  *                        opensource.org/licenses/BSD-3-Clause
  *
  ******************************************************************************
  */
//  BQ76952EVM demo code for STM32 NUCLEO-F103RB + BQ76952EVM 
//
//  Connection description: The I2C SCL and SDA pins are the only pin connections required between the
//  NUCLEO board and the BQ76952EVM for this demo code. Also a ground connection should be made between the 2 boards.
//  The ALERT, RST_SHUT, and DFETOFF pins are also configured on the MCU and can be used as shown.
//
//                                     /|\ /|\ 
//                   STM32             5k |
//                 -----------------    |  5k
//                |             PB8 |---+---|-- I2C Clock (SCL)
//                |                 |       |
//                |		PB9 |-------+-- I2C Data (SDA)
//                |                 |
//     DFETOFF ---| PA8             |
//                |                 |
//   RST_SHUT  ---| PA9             |--- Green LED
//                |                 |
//      ALERT  ---|PA10             |
//                |                 |


/* Includes ------------------------------------------------------------------*/
#include "main.h"

/* Private includes ----------------------------------------------------------*/
/* USER CODE BEGIN Includes */
#include <stdio.h>
#include "BQ769x2Header.h"
/* USER CODE END Includes */

/* Private typedef -----------------------------------------------------------*/
/* USER CODE BEGIN PTD */

/* USER CODE END PTD */

/* Private define ------------------------------------------------------------*/
/* USER CODE BEGIN PD */
#define DEV_ADDR  0x10  // BQ769x2 address is 0x10 including R/W bit or 0x8 as 7-bit address
#define CRC_Mode 0  // 0 for disabled, 1 for enabled
#define MAX_BUFFER_SIZE 10
#define R 0 // Read; Used in DirectCommands and Subcommands functions
#define W 1 // Write; Used in DirectCommands and Subcommands functions
#define W2 2 // Write data with two bytes; Used in Subcommands function
/* USER CODE END PD */

/* Private macro -------------------------------------------------------------*/
/* USER CODE BEGIN PM */

/* USER CODE END PM */

/* Private variables ---------------------------------------------------------*/
I2C_HandleTypeDef hi2c1;

TIM_HandleTypeDef htim1;

UART_HandleTypeDef huart2;

/* USER CODE BEGIN PV */
uint8_t RX_data [2] = {0x00, 0x00}; // used in several functions to store data read from BQ769x2
uint8_t RX_32Byte [32] = {0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 
	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00};
	//used in Subcommands read function
// Global Variables for cell voltages, temperatures, Stack voltage, PACK Pin voltage, LD Pin voltage, CC2 current
uint16_t CellVoltage [16] = {0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00};
float Temperature [3] = {0,0,0};
uint16_t Stack_Voltage = 0x00;
uint16_t Pack_Voltage = 0x00;
uint16_t LD_Voltage = 0x00;
uint16_t Pack_Current = 0x00;

uint16_t AlarmBits = 0x00;
uint8_t value_SafetyStatusA;  // Safety Status Register A
uint8_t value_SafetyStatusB;  // Safety Status Register B
uint8_t value_SafetyStatusC;  // Safety Status Register C
uint8_t value_PFStatusA;   // Permanent Fail Status Register A
uint8_t value_PFStatusB;   // Permanent Fail Status Register B
uint8_t value_PFStatusC;   // Permanent Fail Status Register C
uint8_t FET_Status;  // FET Status register contents  - Shows states of FETs
uint16_t CB_ActiveCells;  // Cell Balancing Active Cells

uint8_t	UV_Fault = 0;   // under-voltage fault state
uint8_t	OV_Fault = 0;   // over-voltage fault state
uint8_t	SCD_Fault = 0;  // short-circuit fault state
uint8_t	OCD_Fault = 0;  // over-current fault state
uint8_t ProtectionsTriggered = 0; // Set to 1 if any protection triggers

uint8_t LD_ON = 0;	// Load Detect status bit
uint8_t DSG = 0;   // discharge FET state
uint8_t CHG = 0;   // charge FET state
uint8_t PCHG = 0;  // pre-charge FET state
uint8_t PDSG = 0;  // pre-discharge FET state

uint32_t AccumulatedCharge_Int; // in BQ769x2_READPASSQ func
uint32_t AccumulatedCharge_Frac;// in BQ769x2_READPASSQ func
uint32_t AccumulatedCharge_Time;// in BQ769x2_READPASSQ func
/* USER CODE END PV */

/* Private function prototypes -----------------------------------------------*/
void SystemClock_Config(void);
static void MX_GPIO_Init(void);
static void MX_I2C1_Init(void);
static void MX_USART2_UART_Init(void);
static void MX_TIM1_Init(void);
/* USER CODE BEGIN PFP */



































void delayUS(uint32_t us) {   // Sets the delay in microseconds.
	__HAL_TIM_SET_COUNTER(&htim1,0);  // set the counter value a 0
	while (__HAL_TIM_GET_COUNTER(&htim1) < us);  // wait for the counter to reach the us input in the parameter
}

void CopyArray(uint8_t *source, uint8_t *dest, uint8_t count)
{
    uint8_t copyIndex = 0;
    for (copyIndex = 0; copyIndex < count; copyIndex++)
    {
        dest[copyIndex] = source[copyIndex];
    }
}

unsigned char Checksum(unsigned char *ptr, unsigned char len)
// Calculates the checksum when writing to a RAM register. The checksum is the inverse of the sum of the bytes.	
{
	unsigned char i;
	unsigned char checksum = 0;

	for(i=0; i<len; i++)
		checksum += ptr[i];

	checksum = 0xff & ~checksum;

	return(checksum);
}

unsigned char CRC8(unsigned char *ptr, unsigned char len)
//Calculates CRC8 for passed bytes. Used in i2c read and write functions 
{
	unsigned char i;
	unsigned char crc=0;
	while(len--!=0)
	{
		for(i=0x80; i!=0; i/=2)
		{
			if((crc & 0x80) != 0)
			{
				crc *= 2;
				crc ^= 0x107;
			}
			else
				crc *= 2;

			if((*ptr & i)!=0)
				crc ^= 0x107;
		}
		ptr++;
	}
	return(crc);
}

void I2C_WriteReg(uint8_t reg_addr, uint8_t *reg_data, uint8_t count)
{
	uint8_t TX_Buffer [MAX_BUFFER_SIZE] = {0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00};
#if CRC_Mode
	{
		uint8_t crc_count = 0;
		crc_count = count * 2;
		uint8_t crc1stByteBuffer [3] = {0x10, reg_addr, reg_data[0]};
		unsigned int j;
		unsigned int i;
		uint8_t temp_crc_buffer [3];

		TX_Buffer[0] = reg_data[0];
		TX_Buffer[1] = CRC8(crc1stByteBuffer,3);

		j = 2;
		for(i=1; i<count; i++)
		{
			TX_Buffer[j] = reg_data[i];
			j = j + 1;
			temp_crc_buffer[0] = reg_data[i];
			TX_Buffer[j] = CRC8(temp_crc_buffer,1);
			j = j + 1;
		}
		HAL_I2C_Mem_Write(&hi2c1, DEV_ADDR, reg_addr, 1, TX_Buffer, crc_count, 1000);
	}
#else 
	HAL_I2C_Mem_Write(&hi2c1, DEV_ADDR, reg_addr, 1, reg_data, count, 1000);
#endif
}

int I2C_ReadReg(uint8_t reg_addr, uint8_t *reg_data, uint8_t count)
{
	unsigned int RX_CRC_Fail = 0;  // reset to 0. If in CRC Mode and CRC fails, this will be incremented.
	uint8_t RX_Buffer [MAX_BUFFER_SIZE] = {0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00};
#if CRC_Mode
	{
		uint8_t crc_count = 0;
		uint8_t ReceiveBuffer [10] = {0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00};
		crc_count = count * 2;
		unsigned int j;
		unsigned int i;
		unsigned char CRCc = 0;
		uint8_t temp_crc_buffer [3];

		HAL_I2C_Mem_Read(&hi2c1, DEV_ADDR, reg_addr, 1, ReceiveBuffer, crc_count, 1000);
		uint8_t crc1stByteBuffer [4] = {0x10, reg_addr, 0x11, ReceiveBuffer[0]};
		CRCc = CRC8(crc1stByteBuffer,4);
		if (CRCc != ReceiveBuffer[1])
		{
			RX_CRC_Fail += 1;
		}
		RX_Buffer[0] = ReceiveBuffer[0];

		j = 2;
		for (i=1; i<count; i++)
		{
			RX_Buffer[i] = ReceiveBuffer[j];
			temp_crc_buffer[0] = ReceiveBuffer[j];
			j = j + 1;
			CRCc = CRC8(temp_crc_buffer,1);
			if (CRCc != ReceiveBuffer[j])
				RX_CRC_Fail += 1;
			j = j + 1;
		}
		CopyArray(RX_Buffer, reg_data, crc_count);
	}
#else
	HAL_I2C_Mem_Read(&hi2c1, DEV_ADDR, reg_addr, 1, reg_data, count, 1000);
#endif
	return 0;
}

void BQ769x2_SetRegister(uint16_t reg_addr, uint32_t reg_data, uint8_t datalen)
{
	uint8_t TX_Buffer[2] = {0x00, 0x00};
	uint8_t TX_RegData[6] = {0x00, 0x00, 0x00, 0x00, 0x00, 0x00};

	//TX_RegData in little endian format
	TX_RegData[0] = reg_addr & 0xff; 
	TX_RegData[1] = (reg_addr >> 8) & 0xff;
	TX_RegData[2] = reg_data & 0xff; //1st byte of data

	switch(datalen)
    {
		case 1: //1 byte datalength
      		I2C_WriteReg(0x3E, TX_RegData, 3);
			delayUS(2000);
			TX_Buffer[0] = Checksum(TX_RegData, 3); 
			TX_Buffer[1] = 0x05; //combined length of register address and data
      		I2C_WriteReg(0x60, TX_Buffer, 2); // Write the checksum and length
			delayUS(2000);
			break;
		case 2: //2 byte datalength
			TX_RegData[3] = (reg_data >> 8) & 0xff;
			I2C_WriteReg(0x3E, TX_RegData, 4);
			delayUS(2000);
			TX_Buffer[0] = Checksum(TX_RegData, 4); 
			TX_Buffer[1] = 0x06; //combined length of register address and data
      		I2C_WriteReg(0x60, TX_Buffer, 2); // Write the checksum and length
			delayUS(2000);
			break;
		case 4: //4 byte datalength, Only used for CCGain and Capacity Gain
			TX_RegData[3] = (reg_data >> 8) & 0xff;
			TX_RegData[4] = (reg_data >> 16) & 0xff;
			TX_RegData[5] = (reg_data >> 24) & 0xff;
			I2C_WriteReg(0x3E, TX_RegData, 6);
			delayUS(2000);
			TX_Buffer[0] = Checksum(TX_RegData, 6); 
			TX_Buffer[1] = 0x08; //combined length of register address and data
      		I2C_WriteReg(0x60, TX_Buffer, 2); // Write the checksum and length
			delayUS(2000);
			break;
    }
}

void CommandSubcommands(uint16_t command) //For Command only Subcommands
// See the TRM or the BQ76952 header file for a full list of Command-only subcommands
{	//For DEEPSLEEP/SHUTDOWN subcommand you will need to call this function twice consecutively
	
	uint8_t TX_Reg[2] = {0x00, 0x00};

	//TX_Reg in little endian format
	TX_Reg[0] = command & 0xff;
	TX_Reg[1] = (command >> 8) & 0xff;

	I2C_WriteReg(0x3E,TX_Reg,2); 
	delayUS(2000);
}

void Subcommands(uint16_t command, uint16_t data, uint8_t type)
// See the TRM or the BQ76952 header file for a full list of Subcommands
{
	//security keys and Manu_data writes dont work with this function (reading these commands works)
	//max readback size is 32 bytes i.e. DASTATUS, CUV/COV snapshot
	uint8_t TX_Reg[4] = {0x00, 0x00, 0x00, 0x00};
	uint8_t TX_Buffer[2] = {0x00, 0x00};

	//TX_Reg in little endian format
	TX_Reg[0] = command & 0xff;
	TX_Reg[1] = (command >> 8) & 0xff; 

	if (type == R) {//read
		I2C_WriteReg(0x3E,TX_Reg,2);
		delayUS(2000);
		I2C_ReadReg(0x40, RX_32Byte, 32); //RX_32Byte is a global variable
	}
	else if (type == W) {
		//FET_Control, REG12_Control
		TX_Reg[2] = data & 0xff; 
		I2C_WriteReg(0x3E,TX_Reg,3);
		delayUS(1000);
		TX_Buffer[0] = Checksum(TX_Reg, 3);
		TX_Buffer[1] = 0x05; //combined length of registers address and data
		I2C_WriteReg(0x60, TX_Buffer, 2);
		delayUS(1000); 
	}
	else if (type == W2){ //write data with 2 bytes
		//CB_Active_Cells, CB_SET_LVL
		TX_Reg[2] = data & 0xff; 
		TX_Reg[3] = (data >> 8) & 0xff;
		I2C_WriteReg(0x3E,TX_Reg,4);
		delayUS(1000);
		TX_Buffer[0] = Checksum(TX_Reg, 4); 
		TX_Buffer[1] = 0x06; //combined length of registers address and data
		I2C_WriteReg(0x60, TX_Buffer, 2);
		delayUS(1000); 
	}
}

void DirectCommands(uint8_t command, uint16_t data, uint8_t type)
// See the TRM or the BQ76952 header file for a full list of Direct Commands
{	//type: R = read, W = write
	uint8_t TX_data[2] = {0x00, 0x00};

	//little endian format
	TX_data[0] = data & 0xff;
	TX_data[1] = (data >> 8) & 0xff;

	if (type == R) {//Read
		I2C_ReadReg(command, RX_data, 2); //RX_data is a global variable
		delayUS(2000);
	}
	if (type == W) {//write
    //Control_status, alarm_status, alarm_enable all 2 bytes long
		I2C_WriteReg(command,TX_data,2);
		delayUS(2000);
	}
}

void BQ769x2_Init() {
	// Configures all parameters in device RAM

	// Enter CONFIGUPDATE mode (Subcommand 0x0090) - It is required to be in CONFIG_UPDATE mode to program the device RAM settings
	// See TRM for full description of CONFIG_UPDATE mode
	CommandSubcommands(SET_CFGUPDATE);

	// After entering CONFIG_UPDATE mode, RAM registers can be programmed. When programming RAM, checksum and length must also be
	// programmed for the change to take effect. All of the RAM registers are described in detail in the BQ769x2 TRM.
	// An easier way to find the descriptions is in the BQStudio Data Memory screen. When you move the mouse over the register name,
	// a full description of the register and the bits will pop up on the screen.

	// 'Power Config' - 0x9234 = 0x2D80
	// Setting the DSLP_LDO bit allows the LDOs to remain active when the device goes into Deep Sleep mode
  	// Set wake speed bits to 00 for best performance
	BQ769x2_SetRegister(PowerConfig, 0x2D80, 2);

	// 'REG0 Config' - set REG0_EN bit to enable pre-regulator
	BQ769x2_SetRegister(REG0Config, 0x01, 1);

	// 'REG12 Config' - Enable REG1 with 3.3V output (0x0D for 3.3V, 0x0F for 5V)
	BQ769x2_SetRegister(REG12Config, 0x0D, 1);

	// Set DFETOFF pin to control BOTH CHG and DSG FET - 0x92FB = 0x42 (set to 0x00 to disable)
	BQ769x2_SetRegister(DFETOFFPinConfig, 0x42, 1);

	// Set up ALERT Pin - 0x92FC = 0x2A
	// This configures the ALERT pin to drive high (REG1 voltage) when enabled.
	// The ALERT pin can be used as an interrupt to the MCU when a protection has triggered or new measurements are available
	BQ769x2_SetRegister(ALERTPinConfig, 0x2A, 1);

	// Set TS1 to measure Cell Temperature - 0x92FD = 0x07
	BQ769x2_SetRegister(TS1Config, 0x07, 1);

	// Set TS3 to measure FET Temperature - 0x92FF = 0x0F
	BQ769x2_SetRegister(TS3Config, 0x0F, 1);

	// Set HDQ to measure Cell Temperature - 0x9300 = 0x07
	BQ769x2_SetRegister(HDQPinConfig, 0x00, 1);  // No thermistor installed on EVM HDQ pin, so set to 0x00

	// 'VCell Mode' - Enable 16 cells - 0x9304 = 0x0000; Writing 0x0000 sets the default of 16 cells
	BQ769x2_SetRegister(VCellMode, 0x0000, 2);

	// Enable protections in 'Enabled Protections A' 0x9261 = 0xBC
	// Enables SCD (short-circuit), OCD1 (over-current in discharge), OCC (over-current in charge),
	// COV (over-voltage), CUV (under-voltage)
	BQ769x2_SetRegister(EnabledProtectionsA, 0xBC, 1);

	// Enable all protections in 'Enabled Protections B' 0x9262 = 0xF7
	// Enables OTF (over-temperature FET), OTINT (internal over-temperature), OTD (over-temperature in discharge),
	// OTC (over-temperature in charge), UTINT (internal under-temperature), UTD (under-temperature in discharge), UTC (under-temperature in charge)
	BQ769x2_SetRegister(EnabledProtectionsB, 0xF7, 1);

	// 'Default Alarm Mask' - 0x..82 Enables the FullScan and ADScan bits, default value = 0xF800
	BQ769x2_SetRegister(DefaultAlarmMask, 0xF882, 2);

	// Set up Cell Balancing Configuration - 0x9335 = 0x03   -  Automated balancing while in Relax or Charge modes
	// Also see "Cell Balancing with BQ769x2 Battery Monitors" document on ti.com
	BQ769x2_SetRegister(BalancingConfiguration, 0x03, 1);

	// Set up CUV (under-voltage) Threshold - 0x9275 = 0x31 (2479 mV)
	// CUV Threshold is this value multiplied by 50.6mV
	BQ769x2_SetRegister(CUVThreshold, 0x31, 1);

	// Set up COV (over-voltage) Threshold - 0x9278 = 0x55 (4301 mV)
	// COV Threshold is this value multiplied by 50.6mV
	BQ769x2_SetRegister(COVThreshold, 0x55, 1);

	// Set up OCC (over-current in charge) Threshold - 0x9280 = 0x05 (10 mV = 10A across 1mOhm sense resistor) Units in 2mV
	BQ769x2_SetRegister(OCCThreshold, 0x05, 1);

	// Set up OCD1 Threshold - 0x9282 = 0x0A (20 mV = 20A across 1mOhm sense resistor) units of 2mV
	BQ769x2_SetRegister(OCD1Threshold, 0x0A, 1);

	// Set up SCD Threshold - 0x9286 = 0x05 (100 mV = 100A across 1mOhm sense resistor)  0x05=100mV
	BQ769x2_SetRegister(SCDThreshold, 0x05, 1);

	// Set up SCD Delay - 0x9287 = 0x03 (30 us) Enabled with a delay of (value - 1) * 15 µs; min value of 1    
	BQ769x2_SetRegister(SCDDelay, 0x03, 1);

	// Set up SCDL Latch Limit to 1 to set SCD recovery only with load removal 0x9295 = 0x01
	// If this is not set, then SCD will recover based on time (SCD Recovery Time parameter).
	BQ769x2_SetRegister(SCDLLatchLimit, 0x01, 1);

	// Exit CONFIGUPDATE mode  - Subcommand 0x0092
	CommandSubcommands(EXIT_CFGUPDATE);
}











//  ********************************* FET Control Commands  ***************************************

void BQ769x2_BOTHOFF () {
	// Disables all FETs using the DFETOFF (BOTHOFF) pin
	// The DFETOFF pin on the BQ76952EVM should be connected to the MCU board to use this function
	HAL_GPIO_WritePin(GPIOA, GPIO_PIN_8, GPIO_PIN_SET);  // DFETOFF pin (BOTHOFF) set high
}

void BQ769x2_RESET_BOTHOFF () {
	// Resets DFETOFF (BOTHOFF) pin
	// The DFETOFF pin on the BQ76952EVM should be connected to the MCU board to use this function
	HAL_GPIO_WritePin(GPIOA, GPIO_PIN_8, GPIO_PIN_RESET);  // DFETOFF pin (BOTHOFF) set low
}

void BQ769x2_ReadFETStatus() { 
	// Read FET Status to see which FETs are enabled
	DirectCommands(FETStatus, 0x00, R);
	FET_Status = (RX_data[1]*256 + RX_data[0]);
	DSG = ((0x4 & RX_data[0])>>2);// discharge FET state
  	CHG = (0x1 & RX_data[0]);// charge FET state
  	PCHG = ((0x2 & RX_data[0])>>1);// pre-charge FET state
  	PDSG = ((0x8 & RX_data[0])>>3);// pre-discharge FET state
}

// ********************************* End of FET Control Commands *********************************

// ********************************* BQ769x2 Power Commands   *****************************************

void BQ769x2_ShutdownPin() {
	// Puts the device into SHUTDOWN mode using the RST_SHUT pin
	// The RST_SHUT pin on the BQ76952EVM should be connected to the MCU board to use this function	
	HAL_GPIO_WritePin(GPIOA, GPIO_PIN_9, GPIO_PIN_SET);  // Sets RST_SHUT pin
}

void BQ769x2_ReleaseShutdownPin() {
	// Releases the RST_SHUT pin
	// The RST_SHUT pin on the BQ76952EVM should be connected to the MCU board to use this function	
	HAL_GPIO_WritePin(GPIOA, GPIO_PIN_9, GPIO_PIN_RESET);  // Resets RST_SHUT pin
}

// ********************************* End of BQ769x2 Power Commands   *****************************************


// ********************************* BQ769x2 Status and Fault Commands   *****************************************

uint16_t BQ769x2_ReadAlarmStatus() { 
	// Read this register to find out why the ALERT pin was asserted
	DirectCommands(AlarmStatus, 0x00, R);
	return (RX_data[1]*256 + RX_data[0]);
}

void BQ769x2_ReadSafetyStatus() { //good example functions
	// Read Safety Status A/B/C and find which bits are set
	// This shows which primary protections have been triggered
	DirectCommands(SafetyStatusA, 0x00, R);
	value_SafetyStatusA = (RX_data[1]*256 + RX_data[0]);
	//Example Fault Flags
	UV_Fault = ((0x4 & RX_data[0])>>2); 
	OV_Fault = ((0x8 & RX_data[0])>>3);
	SCD_Fault = ((0x8 & RX_data[1])>>3);
	OCD_Fault = ((0x2 & RX_data[1])>>1);
	DirectCommands(SafetyStatusB, 0x00, R);
	value_SafetyStatusB = (RX_data[1]*256 + RX_data[0]);
	DirectCommands(SafetyStatusC, 0x00, R);
	value_SafetyStatusC = (RX_data[1]*256 + RX_data[0]);
	if ((value_SafetyStatusA + value_SafetyStatusB + value_SafetyStatusC) > 1) {
		ProtectionsTriggered = 1; }
	else {
		ProtectionsTriggered = 0; }
}

void BQ769x2_ReadPFStatus() {
	// Read Permanent Fail Status A/B/C and find which bits are set
	// This shows which permanent failures have been triggered
	DirectCommands(PFStatusA, 0x00, R);
	value_PFStatusA = (RX_data[1]*256 + RX_data[0]);
	DirectCommands(PFStatusB, 0x00, R);
	value_PFStatusB = (RX_data[1]*256 + RX_data[0]);
	DirectCommands(PFStatusC, 0x00, R);
	value_PFStatusC = (RX_data[1]*256 + RX_data[0]);
}

// ********************************* End of BQ769x2 Status and Fault Commands   *****************************************


// ********************************* BQ769x2 Measurement Commands   *****************************************


uint16_t BQ769x2_ReadVoltage(uint8_t command)
// This function can be used to read a specific cell voltage or stack / pack / LD voltage
{
	//RX_data is global var
	DirectCommands(command, 0x00, R);
	if(command >= Cell1Voltage && command <= Cell16Voltage) {//Cells 1 through 16 (0x14 to 0x32)
		return (RX_data[1]*256 + RX_data[0]); //voltage is reported in mV
	}
	else {//stack, Pack, LD
		return 10 * (RX_data[1]*256 + RX_data[0]); //voltage is reported in 0.01V units
	}

}
void BQ769x2_ReadAllVoltages()
// Reads all cell voltages, Stack voltage, PACK pin voltage, and LD pin voltage
{
  int cellvoltageholder = Cell1Voltage; //Cell1Voltage is 0x14
  for (int x = 0; x < 16; x++){//Reads all cell voltages
    CellVoltage[x] = BQ769x2_ReadVoltage(cellvoltageholder);
    cellvoltageholder = cellvoltageholder + 2;
  }
  Stack_Voltage = BQ769x2_ReadVoltage(StackVoltage);
  Pack_Voltage = BQ769x2_ReadVoltage(PACKPinVoltage);
  LD_Voltage = BQ769x2_ReadVoltage(LDPinVoltage);
}

uint16_t BQ769x2_ReadCurrent() 
// Reads PACK current 
{
	DirectCommands(CC2Current, 0x00, R);
	return (RX_data[1]*256 + RX_data[0]);  // current is reported in mA
}

float BQ769x2_ReadTemperature(uint8_t command) 
{
	DirectCommands(command, 0x00, R);
	//RX_data is a global var
	return (0.1 * (float)(RX_data[1]*256 + RX_data[0])) - 273.15;  // converts from 0.1K to Celcius
}

void BQ769x2_ReadPassQ(){ // Read Accumulated Charge and Time from DASTATUS6 
	Subcommands(DASTATUS6, 0x00, R);
	AccumulatedCharge_Int = ((RX_32Byte[3]<<24) + (RX_32Byte[2]<<16) + (RX_32Byte[1]<<8) + RX_32Byte[0]); //Bytes 0-3
	AccumulatedCharge_Frac = ((RX_32Byte[7]<<24) + (RX_32Byte[6]<<16) + (RX_32Byte[5]<<8) + RX_32Byte[4]); //Bytes 4-7
	AccumulatedCharge_Time = ((RX_32Byte[11]<<24) + (RX_32Byte[10]<<16) + (RX_32Byte[9]<<8) + RX_32Byte[8]); //Bytes 8-11
}

// ********************************* End of BQ769x2 Measurement Commands   *****************************************


/* USER CODE END PFP */

/* Private user code ---------------------------------------------------------*/
/* USER CODE BEGIN 0 */
/* USER CODE END 0 */

/**
  * @brief  The application entry point.
  * @retval int
  */
int main(void)
{
  /* USER CODE BEGIN 1 */

  /* USER CODE END 1 */

  /* MCU Configuration--------------------------------------------------------*/

  /* Reset of all peripherals, Initializes the Flash interface and the Systick. */
  	HAL_Init();

  /* USER CODE BEGIN Init */

  /* USER CODE END Init */

  /* Configure the system clock */
  	SystemClock_Config();

  /* USER CODE BEGIN SysInit */

  /* USER CODE END SysInit */

  /* Initialize all configured peripherals */
  	MX_GPIO_Init();
  	MX_I2C1_Init();
  	MX_USART2_UART_Init();
  	MX_TIM1_Init();
  /* USER CODE BEGIN 2 */
	// Start timer
	HAL_TIM_Base_Start(&htim1);

	HAL_GPIO_WritePin(GPIOA, GPIO_PIN_9, GPIO_PIN_RESET);  // RST_SHUT pin set low
	HAL_GPIO_WritePin(GPIOA, GPIO_PIN_8, GPIO_PIN_RESET);  // DFETOFF pin (BOTHOFF) set low
  	delayUS(10000);
HAL_TIM_Base_Start(&htim1);
	CommandSubcommands(BQ769x2_RESET);  // Resets the BQ769x2 registers
	delayUS(60000);
	BQ769x2_Init();  // Configure all of the BQ769x2 register settings
	delayUS(10000);
	CommandSubcommands(FET_ENABLE); // Enable the CHG and DSG FETs
	delayUS(10000);
	CommandSubcommands(SLEEP_DISABLE); // Sleep mode is enabled by default. For this example, Sleep is disabled to 
									   // demonstrate full-speed measurements in Normal mode. 

	delayUS(60000); delayUS(60000); delayUS(60000); delayUS(60000);  //wait to start measurements after FETs close

  /* USER CODE END 2 */

  /* Infinite loop */
  /* USER CODE BEGIN WHILE */
  while (1)
  {
    /* USER CODE END WHILE */

    /* USER CODE BEGIN 3 */
	
    //Reads Cell, Stack, Pack, LD Voltages, Pack Current and TS1/TS3 Temperatures in a loop
	//This basic example polls the Alarm Status register to see if protections have triggered or new measurements are ready
	//The ALERT pin can also be used as an interrupt to the microcontroller for fastest response time instead of polling
	//In this example the LED on the microcontroller board will be turned on to indicate a protection has triggered and will 
	//be turned off if the protection condition has cleared.

		AlarmBits = BQ769x2_ReadAlarmStatus();
		if (AlarmBits & 0x80) {  // Check if FULLSCAN is complete. If set, new measurements are available
      		BQ769x2_ReadAllVoltages();
      		Pack_Current = BQ769x2_ReadCurrent();
      		Temperature[0] = BQ769x2_ReadTemperature(TS1Temperature);
      		Temperature[1] = BQ769x2_ReadTemperature(TS3Temperature);
			DirectCommands(AlarmStatus, 0x0080, W);  // Clear the FULLSCAN bit
		}
				
		if (AlarmBits & 0xC000) {  // If Safety Status bits are showing in AlarmStatus register
			BQ769x2_ReadSafetyStatus(); // Read the Safety Status registers to find which protections have triggered
			if (ProtectionsTriggered & 1) {
				HAL_GPIO_WritePin(GPIOA, LD2_Pin, GPIO_PIN_SET); }// Turn on the LED to indicate Protection has triggered
				DirectCommands(AlarmStatus, 0xF800, W); // Clear the Safety Status Alarm bits.
			}
		else
		{
			if (ProtectionsTriggered & 1) {
				BQ769x2_ReadSafetyStatus();
				if (!(ProtectionsTriggered & 1)) 
				{
					HAL_GPIO_WritePin(GPIOA, LD2_Pin, GPIO_PIN_RESET);
				} 
			} // Turn off the LED if Safety Status has cleared which means the protection condition is no longer present
		}
		delayUS(20000);  // repeat loop every 20 ms
  }
  /* USER CODE END 3 */
}

/**
  * @brief System Clock Configuration
  * @retval None
  */
void SystemClock_Config(void)
{
  RCC_OscInitTypeDef RCC_OscInitStruct = {0};
  RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};

  /** Initializes the RCC Oscillators according to the specified parameters
  * in the RCC_OscInitTypeDef structure.
  */
  RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSE;
  RCC_OscInitStruct.HSEState = RCC_HSE_ON;
  RCC_OscInitStruct.HSEPredivValue = RCC_HSE_PREDIV_DIV1;
  RCC_OscInitStruct.HSIState = RCC_HSI_ON;
  RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
  RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSE;
  RCC_OscInitStruct.PLL.PLLMUL = RCC_PLL_MUL8;
  if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK)
  {
    Error_Handler();
  }
  /** Initializes the CPU, AHB and APB buses clocks
  */
  RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_HCLK|RCC_CLOCKTYPE_SYSCLK
                              |RCC_CLOCKTYPE_PCLK1|RCC_CLOCKTYPE_PCLK2;
  RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_PLLCLK;
  RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;
  RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV2;
  RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV1;

  if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_2) != HAL_OK)
  {
    Error_Handler();
  }
}

/**
  * @brief I2C1 Initialization Function
  * @param None
  * @retval None
  */
static void MX_I2C1_Init(void)
{

  /* USER CODE BEGIN I2C1_Init 0 */

  /* USER CODE END I2C1_Init 0 */

  /* USER CODE BEGIN I2C1_Init 1 */

  /* USER CODE END I2C1_Init 1 */
  hi2c1.Instance = I2C1;
  hi2c1.Init.ClockSpeed = 400000;
  hi2c1.Init.DutyCycle = I2C_DUTYCYCLE_2;
  hi2c1.Init.OwnAddress1 = 0;
  hi2c1.Init.AddressingMode = I2C_ADDRESSINGMODE_7BIT;
  hi2c1.Init.DualAddressMode = I2C_DUALADDRESS_DISABLE;
  hi2c1.Init.OwnAddress2 = 0;
  hi2c1.Init.GeneralCallMode = I2C_GENERALCALL_DISABLE;
  hi2c1.Init.NoStretchMode = I2C_NOSTRETCH_DISABLE;
  if (HAL_I2C_Init(&hi2c1) != HAL_OK)
  {
    Error_Handler();
  }
  /* USER CODE BEGIN I2C1_Init 2 */

  /* USER CODE END I2C1_Init 2 */

}

/**
  * @brief TIM1 Initialization Function
  * @param None
  * @retval None
  */
static void MX_TIM1_Init(void)
{

  /* USER CODE BEGIN TIM1_Init 0 */

  /* USER CODE END TIM1_Init 0 */

  TIM_ClockConfigTypeDef sClockSourceConfig = {0};
  TIM_MasterConfigTypeDef sMasterConfig = {0};

  /* USER CODE BEGIN TIM1_Init 1 */

  /* USER CODE END TIM1_Init 1 */
  htim1.Instance = TIM1;
  htim1.Init.Prescaler = 63;
  htim1.Init.CounterMode = TIM_COUNTERMODE_UP;
  htim1.Init.Period = 65535;
  htim1.Init.ClockDivision = TIM_CLOCKDIVISION_DIV1;
  htim1.Init.RepetitionCounter = 0;
  htim1.Init.AutoReloadPreload = TIM_AUTORELOAD_PRELOAD_DISABLE;
  if (HAL_TIM_Base_Init(&htim1) != HAL_OK)
  {
    Error_Handler();
  }
  sClockSourceConfig.ClockSource = TIM_CLOCKSOURCE_INTERNAL;
  if (HAL_TIM_ConfigClockSource(&htim1, &sClockSourceConfig) != HAL_OK)
  {
    Error_Handler();
  }
  sMasterConfig.MasterOutputTrigger = TIM_TRGO_RESET;
  sMasterConfig.MasterSlaveMode = TIM_MASTERSLAVEMODE_DISABLE;
  if (HAL_TIMEx_MasterConfigSynchronization(&htim1, &sMasterConfig) != HAL_OK)
  {
    Error_Handler();
  }
  /* USER CODE BEGIN TIM1_Init 2 */

  /* USER CODE END TIM1_Init 2 */

}

/**
  * @brief USART2 Initialization Function
  * @param None
  * @retval None
  */
static void MX_USART2_UART_Init(void)
{

  /* USER CODE BEGIN USART2_Init 0 */

  /* USER CODE END USART2_Init 0 */

  /* USER CODE BEGIN USART2_Init 1 */

  /* USER CODE END USART2_Init 1 */
  huart2.Instance = USART2;
  huart2.Init.BaudRate = 115200;
  huart2.Init.WordLength = UART_WORDLENGTH_8B;
  huart2.Init.StopBits = UART_STOPBITS_1;
  huart2.Init.Parity = UART_PARITY_NONE;
  huart2.Init.Mode = UART_MODE_TX_RX;
  huart2.Init.HwFlowCtl = UART_HWCONTROL_NONE;
  huart2.Init.OverSampling = UART_OVERSAMPLING_16;
  if (HAL_UART_Init(&huart2) != HAL_OK)
  {
    Error_Handler();
  }
  /* USER CODE BEGIN USART2_Init 2 */

  /* USER CODE END USART2_Init 2 */

}

/**
  * @brief GPIO Initialization Function
  * @param None
  * @retval None
  */
static void MX_GPIO_Init(void)
{
  GPIO_InitTypeDef GPIO_InitStruct = {0};

  /* GPIO Ports Clock Enable */
  __HAL_RCC_GPIOC_CLK_ENABLE();
  __HAL_RCC_GPIOD_CLK_ENABLE();
  __HAL_RCC_GPIOA_CLK_ENABLE();
  __HAL_RCC_GPIOB_CLK_ENABLE();

  /*Configure GPIO pin Output Level */
  HAL_GPIO_WritePin(GPIOA, LD2_Pin|GPIO_PIN_8|GPIO_PIN_9|GPIO_PIN_10, GPIO_PIN_RESET);

  /*Configure GPIO pin : B1_Pin */
  GPIO_InitStruct.Pin = B1_Pin;
  GPIO_InitStruct.Mode = GPIO_MODE_IT_RISING;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  HAL_GPIO_Init(B1_GPIO_Port, &GPIO_InitStruct);

  /*Configure GPIO pins : LD2_Pin PA8 PA9 PA10 */
  GPIO_InitStruct.Pin = LD2_Pin|GPIO_PIN_8|GPIO_PIN_9|GPIO_PIN_10;
  GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
  HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);

  /* EXTI interrupt init*/
  HAL_NVIC_SetPriority(EXTI15_10_IRQn, 0, 0);
  HAL_NVIC_EnableIRQ(EXTI15_10_IRQn);

}

/* USER CODE BEGIN 4 */

/* USER CODE END 4 */

/**
  * @brief  This function is executed in case of error occurrence.
  * @retval None
  */
void Error_Handler(void)
{
  /* USER CODE BEGIN Error_Handler_Debug */
  /* User can add his own implementation to report the HAL error return state */

  /* USER CODE END Error_Handler_Debug */
}

#ifdef  USE_FULL_ASSERT
/**
  * @brief  Reports the name of the source file and the source line number
  *         where the assert_param error has occurred.
  * @param  file: pointer to the source file name
  * @param  line: assert_param error line source number
  * @retval None
  */
void assert_failed(uint8_t *file, uint32_t line)
{
  /* USER CODE BEGIN 6 */
  /* User can add his own implementation to report the file name and line number,
     tex: printf("Wrong parameters value: file %s on line %d\r\n", file, line) */
  /* USER CODE END 6 */
}
#endif /* USE_FULL_ASSERT */

/************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/












 

Dear Arjun,

All of TI's sample code can be found here: https://www.ti.com/lit/zip/sluc701. Aside from this, I have a few quick questions.

ARJUN SINGH said:

over UART

1. What device are you trying to use UART with? The BQ769x2 family doesn't contain a UART interface.

ARJUN SINGH said:

BQ79XXX

2. Are you trying to use a BQ769x2 or a BQ79xxx device? Each one requires different code/registers.

3. Did you include pull-up resistors for the I2C on the schematic for your BQ769x2?

4. Do you have a schematic I could view for your setup?

Best,

Asher Nederveld