I2C Touch panel not working in lvgl_guider example with custom display

[patriciocohen]

Hi,

I'm having trouble making an external display touch controller work with my custom IMXRT1062 Board. (The display datasheet is attached). The video part is working perfectly. The only problem is the touch interface via I2C that is not responding.

Via the debugger I got to the LPI2C_MasterTransferBlocking function. Then delving deeper I discovered I that I was getting always a kStatus_LPI2C_ArbitrationLost from LPI2C_MasterCheckAndClearError function.

Using an oscilloscope it can be seen that after the start condition the IMXRT returns both lines to high. This happens when the touch panel I2C lines are connected as well as disconnected. Please see picture below.

Can anyone please help me?

Thank you

Patricio

[patriciocohen · Accepted solution]

I finally solved the problem.

It was that the SION (SOFTWARE INPUT ON) bits for SCL and SDA where not set. Once set, everything works.

I got the answer from here: https://community.nxp.com/t5/i-MX-RT/i-mxRT1021-I2C-slave-address/td-p/1220091

BH

Best regards, 

Patricio