# Cannot read from Pi Zero serial port

**URL:** <https://discourse.nodered.org/t/cannot-read-from-pi-zero-serial-port/17905>\
**Category:** Hardware\
**Created:** [13 November 2019 16:46 UTC](https://discourse.nodered.org/t/cannot-read-from-pi-zero-serial-port/17905 "2019-11-13T16:46:40Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![ghayne](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/ghayne/32/39_2.png) [@ghayne](https://discourse.nodered.org/u/ghayne)\
**Post date:** [13 November 2019 16:46 UTC](https://discourse.nodered.org/t/cannot-read-from-pi-zero-serial-port/17905/1 "2019-11-13T16:46:40Z")

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I am trying to create a serial link between a Pyboard running Micropython and a Pi Zero (Old model with no WiFi) running node-red 1.02.

I cannot receive any data on the pi using the serial port node (v0.9)  
I can send data to the pyboard.  
Loopback on the pyboard works.  
Loopback on the pi does not.

There are no errors while starting and the node-red log also shows normal opening of the port with no errors when I deploy.

[edit] the pi is running buster.

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**Author:** ![dceejay](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/dceejay/32/38_2.png) [@dceejay](https://discourse.nodered.org/u/dceejay)\
**Post date:** [13 November 2019 18:46 UTC](https://discourse.nodered.org/t/cannot-read-from-pi-zero-serial-port/17905/2 "2019-11-13T18:46:20Z")

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pushed a small fix to 0.9.1 - the serialport list was not populating - which won't have helped your situation. (should have been ok if you typed it it - but...)

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**Author:** ![ghayne](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/ghayne/32/39_2.png) [@ghayne](https://discourse.nodered.org/u/ghayne)\
**Post date:** [14 November 2019 15:28 UTC](https://discourse.nodered.org/t/cannot-read-from-pi-zero-serial-port/17905/3 "2019-11-14T15:28:59Z")

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Dave, I hang my head in shame! The problem was a header pin on the Pi that had not been soldered 😱😱😱.