# Can't Receive Simple Serial Comm on Raspberry Pi

**URL:** <https://discourse.nodered.org/t/cant-receive-simple-serial-comm-on-raspberry-pi/74026>\
**Category:** General\
**Created:** [22 January 2023 00:08 UTC](https://discourse.nodered.org/t/cant-receive-simple-serial-comm-on-raspberry-pi/74026 "2023-01-22T00:08:25Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![Gump](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/gump/32/74802_2.png) [@Gump](https://discourse.nodered.org/u/Gump)\
**Post date:** [22 January 2023 00:08 UTC](https://discourse.nodered.org/t/cant-receive-simple-serial-comm-on-raspberry-pi/74026/1 "2023-01-22T00:08:25Z")

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I'm brand new to Node-RED and serial communication setups. I have two Raspberry Pis and I'm attempting to get them to communicate via serial ports. One Pi is using an RS485 CAN HAT, and the other Pi is using a DTech USB RS485 USB adapter.

**Problem:** Both Raspberry Pis appear to transmit fine through their respective serial ports, but neither one shows any receive messages in the debug window.

The Pi with the USB adapter shows a Rx LED and Tx LED at the appropriate time, so I know both devices are transmitting. When the USB adapter is plugged into a PC (not running Node-RED), the message is received and displays without error, so I know the wiring is correct.

It seems simple, what am I missing? I searched the forum, but couldn't find anything helpful.

 ![NodeRed](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/f/e/fe017cb52b62e3b96811db314e14119bcbf703c2.png)

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**Author:** ![Colin](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/colin/32/17040_2.png) [@Colin](https://discourse.nodered.org/u/Colin)\
**Post date:** [22 January 2023 08:00 UTC](https://discourse.nodered.org/t/cant-receive-simple-serial-comm-on-raspberry-pi/74026/2 "2023-01-22T08:00:58Z")

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Welcome to the forum @Gump

In the serial config node, where you set the bandwidth, what option have you set for splitting the data coming in? If you have told it to wait for a particular character, perhaps that character never arrives.

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**Author:** ![system](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/1X/d073cd938eafa2e558d7c2cd59003b3ef4963033.png) [@system](https://discourse.nodered.org/u/system)\
**Post date:** [5 February 2023 08:01 UTC](https://discourse.nodered.org/t/cant-receive-simple-serial-comm-on-raspberry-pi/74026/3 "2023-02-05T08:01:26Z")

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