Kishore Bolisetti

K65 I2C DMA Slave operation

Discussion created by Kishore Bolisetti on Dec 28, 2018
Latest reply on Jan 2, 2019 by Jing Pan

I have configured K65 controller in slave mode. When master sends a read request, i am responding with a set of 'n' number of bytes as a response, but interestingly i always see the first byte received on the master (I am using a PC based I2C tool) side is the slave ID. Per my understanding when master sends a read request, it sends slave ID, then i respond with set of bytes, not sure why i am seeing this extra byte on the master side?

 

Since the last byte i received is the slave ID, i am not sure if that byte within the data register is transmitted out first before the intended number of bytes transfer. I am using DMA to send the response.

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