Serial in node not working in node-red 0.20.5

General
1

I'm running node-red 0.20.5 on an RPi 3 B+ with Raspbian GNU/Linux 9.8 (stretch) and node-red-serial-port 0.8.1. Since upgrading from node-red 0.19.5, the serial in node has started behaving strangely.

Messages are being transmitted from another PCB to the RPi every second, but mostly I get no data. Every few minutes I get either a "-1" message or garbage such as this: "�~�����~��?���~���~?���~��~?~��~?�~��~���~���~�~�~����~����~��~?�~��~���~�����~��?���~���~?���~��~?~��~?�~��~���~���~�~�~����~����~��~?�~��~���~�����~��?���~���~?���~��~?~��~?�~���~���~���~�~�~����~����~��~?�~��~���~�����~��?���~���~?���~��~?~��~?�~��~���~���~�~�~����~����~��~?�~��~���~�����~��?���~���~?���~��~?~��~?�~��~���~���~�~�~����~����~��~?�~��~���~�����~��?���~���~?���~��~?~��~?�~��~���~���~�~�~����~����~��~?�~��~���~�����~��?���~���~?���~��~?~��~?�~��~���~���~�~�~����~��~~��~��~?�~��~���~�����~��?���~���~?���~��~?~��~?�~��~���~���~�~�~����~��~..."

I should be receiving a short string every second about 16 bytes long and terminated with '\r' (CR, ASCII character 13).

Any clues as to what has changed between 0.19.5 and 0.20.5 that could cause this?

2

Issue resolved. For some reason the configuration for ttyS0 was changed so that the baud rate became 57600 instead of 9600. This never occurred in previous upgrades of node-red, so I'm still a little confused as to how this happened. Any thoughts?

3

How did you upgrade?

4

Typically I use the update-nodejs-and-nodered script. However, I've traced this issue to (shockingly) an error on my part. I started working with a new serial device that runs at a higher baud rate and that configuration got copied into the wrong flow. Sorry to waste your time.

5

No problem.