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ChipworkX to Panda serial connection loses bytes


#1

Hello,

First, happy new year :slight_smile:

I have bugged you before about the UART communication between ChipworkX and Panda. Now, at more advanced phase of development, I have encountered another problem.
The communication generally works fine. That is until yesterday when I noticed something strange. It looks like some bytes cannot be transfered through the port. More specifically byte 17 (00010001) and 19(00010011) can’t seem to get transfered.
What I did is to use logic analyzer. When connected to the ChipworkX and Panda’s serial transmit pins, it can read all the data being sent (including bytes 17 and 19).
The bytes, however, never get to the receive pin of the UART.
The communication works fine with any other byte, only these two prove problematic.

So, to generalize, the problem seems to be that bytes 17 and 19 can be sent, but not received on the other end. Both microcontrollers have the 4.1 firmware (I believe it it the last one).
If there is anyone else having the same problem, please do share :slight_smile:

Thanks!


#2

are you enabling xON/xOFF protocol?

Look here and you will see 17 and 19, just like you said :slight_smile: http://en.wikipedia.org/wiki/Software_flow_control


#3

Thanks a lot, Gus! You saved me a lot of trouble :slight_smile: