I2C Problem with STM32F103ze and Sensor

[sam239955]

Posted on February 20, 2012 at 21:28

Hi,

according to my thread in my native language (german): http://www.mikrocontroller.net/topic/249457&sharp2558731

I wanted to find a solution for my problem.

I have Keil + STM32F103ZE + ITG3200 (http://invensense.com/mems/gyro/documents/PS-ITG-3200-00-01.4.pdf Gyroscope Sensor. Connected on I2C1 and a second ITG3200 sensor on I2C2.

At the moment I'm trying to read out the sensor on I2C1. But I get stucked in the line:

/* Test on EV5 and clear it */

while

(!I2C_CheckEvent(ITG_I2C, I2C_EVENT_MASTER_MODE_SELECT)); and Line: ErrorStatus I2C_CheckEvent(I2C_TypeDef* I2Cx, uint32_t I2C_EVENT) in the STM32f10x_i2c.c I directly connected SCL (PB6) to the Sensor SCL and the SDA (PB7) to SDA.

My Board uses a 16mhz HSE and the Std.Lib is configured for that.

At the Screenshots in the first links you will see the Clock's and I2C Registers

I attached my code.

Maybe some one has a solution.

Thanks for help

with regards

Sven

//Links:

Link to sensor manual: http://invensense.com/mems/gyro/documents/PS-ITG-3200-00-01.4.pdf

#i2c-stm32

[sam239955]

Posted on February 20, 2012 at 23:29

I have no Pullups on the sensor SCL SDA Wire ... is that maybe the problem?

Its the only sensor at the Port and the distance is 1cm to the mcu.

[emalund]

Posted on February 20, 2012 at 23:35

very likely.

you MAY be limping along with internal pullups, but a reasonably low pullup resistance is essential for a well performing I²C bus.

ALSO read the errata, the  I²C in the f1xx requires a lot of TLC

Erik

[sam239955]

Posted on February 20, 2012 at 23:52

yes its horrible !

Thats why i used the working code from the ST -INEMO Board.