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NodeMCU v3 RX (d9/gpio3) pin doesn't see data #583

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LionBS76 opened this issue Sep 23, 2024 · 2 comments
Open

NodeMCU v3 RX (d9/gpio3) pin doesn't see data #583

LionBS76 opened this issue Sep 23, 2024 · 2 comments

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@LionBS76
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Hello.

Flashed esp-link latest stable ver to NodeMCU v3 with CH340 chip.
Flashed nodeMCU works in such ways:

  • Web interface works;
  • WiFi works;
  • Terminal communication trough builtin USB port (CH340 chip, USB-TTL) works. I can send to NodeMCU and receive from NodeMCU;

When I try to use RXD0 & TXD0 (GPIO3 & GPIO1) pins to connect to external USB-TTL board then I can only send data from NodeMCU. So only TX works. And can't receive any data on RX pin from USB (COM port) !

When I swap serial from Web interface and reconnect on the fly external USB-TTL board to RXD2 & TXD2 (GPIO13 & GPIO15) then communication through external USB port (USB-TTL) start working !
But if I reload (plug out and plug in) NodeMCU with swaped RX/TX config and connected external USB-TTL board to RXD2 & TXD2 (GPIO13 & GPIO15) pins then NodeMCU doesn't start at all !

@LionBS76
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Hello.

Flashed esp-link latest stable ver to NodeMCU v3 with CH340 chip. Flashed nodeMCU works in such ways:

  • Web interface works;
  • WiFi works;
  • Terminal communication trough builtin USB port (CH340 chip, USB-TTL) works. I can send to NodeMCU and receive from NodeMCU;

When I try to use RXD0 & TXD0 (GPIO3 & GPIO1) pins to connect to external USB-TTL board then I can only send data from NodeMCU. So only TX works. And can't receive any data on RX pin from USB (COM port) !

When I swap serial from Web interface and reconnect on the fly external USB-TTL board to RXD2 & TXD2 (GPIO13 & GPIO15) then communication through external USB port (USB-TTL) start working ! But if I reload (plug out and plug in) NodeMCU with swaped RX/TX config and connected external USB-TTL board to RXD2 & TXD2 (GPIO13 & GPIO15) pins then NodeMCU doesn't start at all !

Try to answer on ,y own question/problem :)
Seems that this is NodeMCU/Wemod D1 mini (and similar dev boards) problem. This dev boards have USB-TTL converter and RX pin always stay HIGH so there is no possibility to use it for normal communication.
Have to use ESP-01 and so on.

@uzi18
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uzi18 commented Oct 3, 2024

@LionBS76 try to use 3.2.x version with many fix-es

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