I2C reading troubles from TPS 65950.

Hi,

I am having troubles working with the i2c module on the beagle board. I am writing a bare metal program (no OS support). I have a routine to initilize i2c, read bytes and write bytes. I am able to toggle the LED connected to the TPS65950 - I can write to the register and read back the data that I just wrote. However, when I attempt to read the register 0x0 and 0x1 of the group 0x48 (The vendor ID registers), all I get is a value of 0. The same code runs fine and returns 0x51 and 0x04 when I run it on qemu.

Could anyone share their insight into this? I have been trying this on and off for weeks now.

Thank you.

hey which led you are turning off is it D5.
if D5 than plz can you post what you done.
thank you.

This post is from 2011. I lost that beable board nearly an year ago - a little mechanical pressure and the I2C bus stopped working - So no power management was possible. I can tell you what I discovered.

If I boot from the Flash after a power cycle, the I2C works perfect.
If I boot from the SD Card after a power cycle, the I2C does not work.

Once booted from the flash, subsequent boots from the SD card without power cycling lets the I2C work.

This was from a long time ago, so I hope I am not making any mistakes.

Lord Bharath Bhushan Lohray

महामहिम भरत भूषण लोहरे

To Answer your specific question about the D5 LED - I really do not remember anymore :frowning:

Lord Bharath Bhushan Lohray

महामहिम भरत भूषण लोहरे

then how to toggle the gpio of tps65950 from beagleboard xm
do your remember any command

Unfortunately, no :frowning:

Lord Bharath Bhushan Lohray

महामहिम भरत भूषण लोहरे