Has anyone used the AR1020 touch controller? If so do you know if it runs at 400Khz or is it limited to 100Khz. I am using the I2C format to clock the data in and out.

The reason I ask is I can talk to it for a read at either speeds(exception of after a write odd code required) but I can't write to it but at 100Khz.

I get a response at 400Khz after a write command of error code $03 which is unrecognized header. It actually takes some usually code just to get the response so I figure it is not recognizing what i am sending. Just stumps me that the read seems to work on pen interrupt trigger but not when sending a command.

I couldn't find where it states this in the data sheet as far as the speed but I did find some examples in SPI mode where it was limited in speed but I wasn't sure how that affected the
I2C speed since it is usually lower than SPI.