LSM303AGR, Accelerometer Read Address cannot be auto-incremented.

[Min-Kyoung Kim]

Hi, I'm using LSM303AGR.

I cannot read acceleromter 6bytes from 0x28 _ 0x2D.

It is read only 0x28 register 6 times.

I tried to read other register, 0x20 0x21, etc...

Likewise, It is read only first address register 6 times or several times.

I also checked MS bit (bit1). it is 1 of course.

BUT!

It works Magnetometer same way!

I can read 6 registers magnetometer data.

Below Configure values.

1. ODR : 1001 (1.344kHz)
2. LPen : normal mode
3. Zen, Yen, Zen : 1
4. BDU : 0
5. BLE : 0
6. FS : 10 (8g)
7. HR : 1
8. ST : 00
9. SPI_ENABLE : 1 (3 wire)

Below, my configuration code and reading code

	Sensor_IO_SPI_CS_Enable(&SensorHandle[ACCEL]);
	valueTx = 0x29;	//8g(Sensitivity : 3.9 mG/LSB), HR mode, 3 wire
	Sensor_IO_SPI_Write(&SensorHandle[ACCEL],LSM303AGR_ACC_CTRL_REG4,&valueTx,1);
	Sensor_IO_SPI_CS_Disable(&SensorHandle[ACCEL]);
 
	Sensor_IO_SPI_CS_Enable(&SensorHandle[ACCEL]);
	valueTx = 0x97;  //1.344kHz, no power down(12bit, divisor : 16), x,y,z enabled
	Sensor_IO_SPI_Write(&SensorHandle[ACCEL],LSM303AGR_ACC_CTRL_REG1,&valueTx,1);
	Sensor_IO_SPI_CS_Disable(&SensorHandle[ACCEL]);

	Sensor_IO_SPI_CS_Enable(ctx);
        Sensor_IO_SPI_Read(ctx,ctx->RegRX, raw_data_tmp.u8bit,6);
        Sensor_IO_SPI_CS_Disable(ctx);

[Eleon BORLINI · Accepted solution]

Hi, the configuration should be ok, and magnetometer and accelerometer SPI communication should behave in the same way. Also in case of the magnetometer the MS bit is =1? Is it possible for you to share the oscilloscope pattern?

[Min-Kyoung Kim]

I didn't know that the acceleromter ​register address is 7 bits.

I didn't set the MS bit to =1.

When I compared MS bit between accel and mag, I got it thank for your comment.

Thank you.

[Eleon BORLINI]

​you're welcome