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jmgiacalone
11-09-2012, 08:00 PM
Hello,

This may seem like a silly question, but I wanted to sanity check my thinking on this. I am currently playing with porting firmware for running a RepRap 3D printer to Teensy 3.0, in which the PC host software uses the USB Serial to send commands to the firmware. Currently, the data contains line numbers and a checksum to ensure data integrity over historically potentially noisy serial lines.

Since the USB Serial channel only presents itself as a Serial port, but is actually a proper USB channel, am I correct in thinking this error checking is redundant? In all tests to date, I've yet to find any communication errors using the USB Serial to send data to Teensy 3.0.

Thank for any advice on this.

Paul
11-09-2012, 09:38 PM
Yes, USB has error checking on every packet (with automatic retransmit) and end-to-end flow control on every endpoint, so the error checking within the serial data is redundant. But it probably adds only minimal overhead.

jmgiacalone
11-10-2012, 07:49 PM
Thanks Paul!