PuTTY not able to write to the ESP COM port

[justinmreina]

Hi,
I am getting started with Espressif development and having trouble allowing write access from PuTTY to my ESP32.

Setup:

1. ESP32-S3-WROOM-1 ← (ESP32-S3-Touch-LCD-4.3B-BOX)
2. USB connection from 4.3B-BOX module to PC using PuTTY (Win11)
   1. driver - system32\drivers\usbuser.sys

Working:

• ESP->PuTTY transmit

Not-working:

• PuTTY->ESP transmit (similar - Golioth: ESP-IDF monitor READ only)

Status: (from ESP-IDF Serial Monitor)

--- Warning: Writing to serial is timing out. Please make sure that your application supports an interactive console and that you have picked the correct console for serial communication.

Why won't writes work from PuTTY? I have tried in ESP-IDF Serial Monitor and with a serial connection in LabVIEW observing the same effect. How can I get my ESP serial port receiving bytes from PuTTY? I tried the Golioth forum idea above but that didn't work for me. This is strange!

[teletypeguy]

I don't use putty but I use CoolTerm all the time and it works well with the usb serial port that I run at the default 115200 as well as uart1 and uart2 ports I stream at 230400.

The usb connection on an esp dev board just looks like a com port to windows and it is uart0 in idf. By using the Monitor button in the ide you get the normal display -- I have a task that handles rx characters that I send to do various test things -- here I type in a little command !*#97 that dumps some info:
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When I connect coolterm (cannot have the ide running as it holds the com port open) and connect to the same com port, I can do the same thing (here you see the ansi color prefix sequences):
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Coolterm can also be configured to display in color:
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Not sure why you are having a problem with putty.