<![CDATA[UART over Pyscan pins]]>Hi everyone.

I'd like to know whether I can use existing pins on the pyscan board to communicate with another device via UART. Can't find anything on the matter. I would for example like to use the fingerprint reader's RX/TX pins as my UART pins. Currently using it with a SiPy, if that helps.

Any help is appreciated. Thanks, Louis

]]>https://forum.pycom.io/topic/6803/uart-over-pyscan-pinsRSS for NodeMon, 11 May 2026 02:40:18 GMTWed, 03 Feb 2021 20:37:43 GMT60<![CDATA[Reply to UART over Pyscan pins on Wed, 03 Feb 2021 20:37:43 GMT]]>Hi everyone.

I'd like to know whether I can use existing pins on the pyscan board to communicate with another device via UART. Can't find anything on the matter. I would for example like to use the fingerprint reader's RX/TX pins as my UART pins. Currently using it with a SiPy, if that helps.

Any help is appreciated. Thanks, Louis

]]>https://forum.pycom.io/post/36915https://forum.pycom.io/post/36915Wed, 03 Feb 2021 20:37:43 GMT<![CDATA[Reply to UART over Pyscan pins on Thu, 04 Feb 2021 07:03:51 GMT]]>@Louis-Henn You cannot share UART TX signals, because they are driven actively both high and low. But you can use the pins on the extension connector of Pyscan for UART. See: https://docs.pycom.io/gitbook/assets/pyscan-pinout.pdf. Using P15 and P19 for UART looks fine, as long as the fingerprint reader is not connected. Just give it a try.

]]>https://forum.pycom.io/post/36918https://forum.pycom.io/post/36918Thu, 04 Feb 2021 07:03:51 GMT<![CDATA[Reply to UART over Pyscan pins on Thu, 04 Feb 2021 10:06:56 GMT]]>@robert-hh thank you. I guess my next question is how would I program UART to work over this pins. Up to know I've used pins 10 and 11 when using pymakr expansion board. How would I code it to be P15/P19. Is it just conncted to GPIO 15/19? Edit: I just saw there is no GPIO 19

]]>https://forum.pycom.io/post/36920https://forum.pycom.io/post/36920Thu, 04 Feb 2021 10:06:56 GMT<![CDATA[Reply to UART over Pyscan pins on Thu, 04 Feb 2021 10:10:56 GMT]]>@Louis-Henn Look at the documentation: https://docs.pycom.io/firmwareapi/pycom/machine/uart/
e.g.

from machine import UART
uart = UART(1, baudrate=9600, pins=('P19', 'P15'))

or uart 1. Note, that using uart.init() requires specifying all setting again, so it is more convenient to put all setting in the uart instantiation call.

]]>https://forum.pycom.io/post/36921https://forum.pycom.io/post/36921Thu, 04 Feb 2021 10:10:56 GMT<![CDATA[Reply to UART over Pyscan pins on Thu, 04 Feb 2021 13:02:42 GMT]]>@robert-hh took some debugging, but I did manage to make it work like you said. Thanks a lot!

]]>https://forum.pycom.io/post/36922https://forum.pycom.io/post/36922Thu, 04 Feb 2021 13:02:42 GMT