# Serial pin in node-red
**URL:** https://dietpi.com/forum/t/serial-pin-in-node-red/18194
**Category:** Troubleshooting
**Created:** [21 October 2023 22:02 UTC](https://dietpi.com/forum/t/serial-pin-in-node-red/18194 "2023-10-21T22:02:42Z")
**Posts on this page:** 3
**Page:** 1
### Author:  [@jjcampis](https://dietpi.com/forum/u/jjcampis)
#### Post date: [21 October 2023 22:02 UTC](https://dietpi.com/forum/t/serial-pin-in-node-red/18194/1 "2023-10-21T22:02:42Z")
hi, i have an installation of node-red with gpio but when i connect an esp32 Tx pin to Rx pin of rpi4 it doesnt show what it sends if i put only gpio pin it shows 0 and 1 (assuming it’s sending something)
now im trying to enable serial uart ttyS0 or something via dietpi-config but im stuck.
please help.
thanks in advice!
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### Author:  [@jjcampis](https://dietpi.com/forum/u/jjcampis)
#### Post date: [22 October 2023 00:01 UTC](https://dietpi.com/forum/t/serial-pin-in-node-red/18194/2 "2023-10-22T00:01:59Z")
i´ve found this topic:
> [@Cannot connect serial port(uart) to Node red Raspberry Pi](https://dietpi.com/forum/t/cannot-connect-serial-port-uart-to-node-red-raspberry-pi/15215):
>
> Hello, the topic is old, but I’m bringing it up again. I’m trying to connect a serial port (UART) to Node red but I’m not having any success. Can you explain in detail how the access to the serial port in Dietpi is organized, because from enough attempts, all of them have been unsuccessful. What is /dev/ttyS0 and /dev/ttyAMA0? In both cases, I get not connected in Node red. As far as I know, one port is software and the other is hardware, but both ports available in Node red are the same.
that says you have to add nodered to group dialout but… no success
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### Author:  [@jjcampis](https://dietpi.com/forum/u/jjcampis)
#### Post date: [22 October 2023 04:11 UTC](https://dietpi.com/forum/t/serial-pin-in-node-red/18194/3 "2023-10-22T04:11:59Z")
I apologize… The Rx pin was working fine… my mistake was connecting an esp32 through the Tx2 pin… if it was Tx0 there would be no problem, I simply changed my programming on esp32 and everything is fine.