Public Access
14 lines
873 B
Markdown
14 lines
873 B
Markdown
 
|
# Wiring between ESP32 and Nano
|
||
|
|
|
||
|
|
[← Back to the README](../README.md)
|
||
|
|
|
||
|
|
The ESP32 talks to the Nano on **UART2** (`Serial2`, 115200 baud). The ESP32's own
|
||
|
|
`Serial` (UART0, USB) is free for debug output.
|
||
|
|
|
||
|
|
| ESP32 | Nano | Notes |
|
||
|
|
|-------|------|-------|
|
||
|
|
| GPIO 17 (TX2) | D0 (RX) | Display commands |
|
||
|
|
| GPIO 16 (RX2) | D1 (TX) | `READY` and `ERR` replies, and bootloader answers when flashing over WiFi. Use a 5 V → 3.3 V voltage divider (e.g. 1 kΩ / 2 kΩ), because the ESP32 is not 5 V tolerant. Without it, the ESP waits a fixed 3 s after power-on, and `nano_ota` doesn't work. |
|
||
|
|
| GPIO set in `NANO_RESET_PIN` | RESET (through an NPN transistor) | Optional, only needed to flash a Nano with Optiboot over WiFi. See [Bootloaders](nano-ota.md#bootloaders). |
|
||
|
|
| GND | GND | Common ground |
|
||
|
|
| GPIO 13 | Relay input | Relay powers the panels and the Nano (`LOW` = on) |
|