Hello,
Based on this article: https://openwrt.org/docs/guide-user/hardware/esp8266-serial-bridge#pinout it is possible to power up 3,3V devices like the ESP32 or ESP8266 boards straight from some of the TP-Link and Xiaomi router's UART TTL pins.
I am currently doing a project which requires these boards to operate, and I tought I would "integrate" these into the XIoami router's enclosures, as there is sufficient extra space in them (after soldering the required pins).
I want to achieve the oppisite that this article mentions. After plugging the required VCC, TX and RX pins, Is it possible to use the UART pins as a serial console client with screen or minicom or whatever, in OpenWrt, example to connect to the (depending what is currently running on the said ESPxxx board) ESPxxx boards serial terminal from OpenWrt itself (after once I am connected with SSH to OpenWrt for example)? Has anyone done such thing before? I would be rather useful to also have a "remote" monitor/debug feature too, beside this rather nice possibility to draw power to these boards too (one does not need an additional power supply).
Based on this Wiki article: https://openwrt.org/docs/techref/hardware/port.serial it is mentioned that there is possible to connect from one OpenWrt board with another one by interconnecting both boards through UART, so I guess is possible...