HAL_I2C_Mem_Read returns nothing?

[MÇETİ.1]

I use MAX9611 to measure current. It has 2 register to read current. 12 bits divides 2 bytes. MSB(8 bits) and LSB(4 bits). I tried to read only MSB but I couldn't, Can anyone help me?

 Note: there is no externall pull up res, I configure an internal pull up.
I write a simple code. HAL_I2C_IsDeviceReady return HAL_OK. But when I debug HAL_I2C_Mem_Read returns nothing

 uint16_t deviceAdress = 0xE1;
 
uint16_t regAdress = 0x02;
 
uint8_t CurVal;
 
 
 
void isDeviceReady()
 
{
 
	HAL_StatusTypeDef status;
 
	status = HAL_I2C_IsDeviceReady(&hi2c1, deviceAdress, 1, 50);
 
 
 
	if(status == HAL_OK)
 
	{
 
		return 1;
 
	}
 
	else
 
		return 0;
 
}
 
 
 
while(1)
 
{
 
isDeviceReady();
	 HAL_GPIO_WritePin(ENABLE_M_GPIO_Port, ENABLE_M_Pin, 1); // Enables mosfet
	 HAL_I2C_Mem_Read(&hi2c1, deviceAdress, reg_adress, 1, &CurVal, 1, 100);
 
}

https://eu.mouser.com/datasheet/2/609/MAX9611_MAX9612-3131515.pdf

[Pavel A.]

void isDeviceReady... returns 1? Really? Please make a habit to fix all compiler error AND warnings.

Call HAL_I2C_Mem_Read only after isDeviceReady returns 1.

> uint16_t deviceAdress = 0xE1;

Suspicious... the lowest bit of device address normally is 0.

Though the ST library always sets this address bit correctly for the function, so 0xE1 may work as is.

[MÇETİ.1]

First of all thank you for your reply,

I wondered how could I check if line is idle and search for it. I saw it in a video and I implemented it. When I debug code, it returns HAL_OK every time. But I will check and make it in a proper way.

I check MAX9611's datasheet, to read data device adress 0XE1 and write adress is 0xE1 in my device's condition. MAX9611's A0 and A1 pins connected to GND.

For reading, first I send a data in int main, it is how it is written like this in datasheet.

And then in while(1)

isDeviceReay();

HAL_I2C_Mem_Write(&hi2c1, 0xE0, 0x02, 1, CurVal, 1, 100);

HAL_GPIO_WritePin(ENABLE_M_GPIO_Port, ENABLE_M_Pin, 1); // Enables mosfet

HAL_I2C_Mem_Read(&hi2c1, 0xE1, 0x02, 1, CurVal, 1, 100);

I observe load draws 500mA from powersupply when I open mosfet. But buffer is empty.

When I read temperature register(0x08) it turns 128. This is not possible either.