My code is working fine using ESP32 boards version 1.0.6, but after upgrading to version 2.0.0 I get the following error when initializing second hardware serial port,
E (64) uart: uart_set_pin(595): tx_io_num error
ESP_ERROR_CHECK failed: esp_err_t 0xffffffff (ESP_FAIL) at 0x4008ba60
file...
Following these instructions you have access to the 3 hardware serials on an ESP32.
Serial0 is connected to the USB interface.
The default pins are
Serial0 - RX: GPIO3 , TX: GPIO1
Serial1 - RX: GPIO9 , TX: GPIO10
Serial2 - RX: GPIO16 , TX: GPIO17
On a TTGO Lora board the GPIO 9,10,16,17 are...