I2C HAL_I2C_Mem_Read ( ) failed

this code works:

note the address is shifted up 1 bit...

#define MCP4728_DacAddress 0x60 << 1

void write4Dacs(void) {
 char buf[16];
 
 struct DacIIC MCP4728IIC; 
 HAL_StatusTypeDef IIC_Response;
 
 // Dac_Value = (4096 * 1) / 5; // 1V
 
 //Channel 0
 MCP4728IIC.DacTxBuffer[0] = (Dac0_Value & 0x0f00) >> 8;
 MCP4728IIC.DacTxBuffer[1] = Dac0_Value & 0x00ff;
 
 //Channel 1
 Dac1_Value = Dac0_Value + (4096 * 1) / 5; // 1V
 MCP4728IIC.DacTxBuffer[2] = (Dac1_Value & 0x0f00) >> 8;
 MCP4728IIC.DacTxBuffer[3] = Dac1_Value & 0x00ff;
 
 //Channel 2
 Dac2_Value = Dac1_Value + (4096 * 1) / 5; // 2V
 MCP4728IIC.DacTxBuffer[4] = (Dac2_Value & 0x0f00) >> 8;
 MCP4728IIC.DacTxBuffer[5] = Dac2_Value & 0x00ff;
 
 //Channel 3
 Dac3_Value = Dac2_Value + (4096 * 1) / 5; // 3V
 MCP4728IIC.DacTxBuffer[6] = (Dac3_Value & 0x0f00) >> 8;
 MCP4728IIC.DacTxBuffer[7] = Dac3_Value & 0x00ff;
 
 //DAC_IIC.write(DAC_ADDR + (Dac_Address << 1), buf, 8); 
 IIC_Response = HAL_I2C_Master_Transmit(&hi2c1, MCP4728_DacAddress, &MCP4728IIC.DacTxBuffer[0], 8, 10);
 
 
}

The issue is I2C_FLAG_BUSY is always SET. That's why this function bailed out after timeout.

We are using 24AA02E48 to get EUI-48. Thx

static HAL_StatusTypeDef I2C_WaitOnFlagUntilTimeout(I2C_HandleTypeDef *hi2c, uint32_t Flag, FlagStatus Status, uint32_t Timeout, uint32_t Tickstart)

{

 while (__HAL_I2C_GET_FLAG(hi2c, Flag) == Status)

I checked the I2C registers. ISR register value is 0x8009 (1000000000001001) which means bit 15 is set in HAL_I2C_Mem_Read() function.

I also check the flag before call read. Not sure how to turn it off.

uint32_t flag = __HAL_I2C_GET_FLAG(m_i2c, I2C_FLAG_BUSY);

Bit 15 BUSY: Bus busy

This flag indicates that a communication is in progress on the bus. It is set by hardware when a

START condition is detected. It is cleared by hardware when a STOP condition is detected, or

when PE=0.

Sorry to catchup, which part ?

what address are you using ?

on initisation the errent flag is set or not ?

try power off and then check the flag it should be clear.

then check the DAC code I sent... I don't check any flags, it just works.

which part ? and what address is it ?

and show us the first line of transmit.

I am using STM32L4A6VG MCU connecting I2C 2 to Microchip 24AA02E48 EEPROM (2K I2C Serial EEPROMs with EUI-48™ or EUI-64™ Node Identity) for EUI-48 ID.

http://ww1.microchip.com/downloads/en/DeviceDoc/20002124G.pdf

There is no transition happened at all since all of checking before TX/RX. I am able to DISABLE/ENABLE I2C to make the first BUSY flag go away. Now I am seeing this TXIS flag is not set. Thx

 /* Wait until TXIS flag is set */

 if (I2C_WaitOnTXISFlagUntilTimeout(hi2c, Timeout, Tickstart) != HAL_OK)

how are the pins A0 A1 A2 set ? 0,0,0 ?

thats 0xA0 for Write and 0xA1 for Read,

are you using just one device on the IIC bus ?

in my code there is no initialisation, it just works...

Thanks for the input. Just figured out the way our layers of driver works should OR 0x01 before calling 24AA02E48 driver. Thanks a lot.

m_i2c->read_from_address(0b10100000, 0xFA, 1, in_data, in_len);

I still have the same error with the READ address modified. Thx

I guess you are using blocking code, and you are read/nested read/nested read/stopped/// I guess

can you try this ?

POWER OFF for 5 seconds

READ ONCE only.

wait 1 second

READ again

m_i2c->read_from_address(0b10100000, 0xFA, 1, in_data, in_len);

that's incorrect.

read is 0b10100001