ESP32 Forum

file:

#define ECHO_TEST_TXD (16)
#define ECHO_TEST_RXD (17)
#define ECHO_TEST_RTS (2)
#define ECHO_TEST_CTS (15)

uart_set_pin(uart_num, ECHO_TEST_TXD, ECHO_TEST_RXD, ECHO_TEST_RTS, ECHO_TEST_CTS);

question:
if here have set ECHO_TEST_RTS, ECHO_TEST_CTS,
can we re define these two pins: ECHO_TEST_RTS, ECHO_TEST_CTS as other GPIO

Try to use UART_PIN_NO_CHANGE.
By the way, in uart_set_pin, the driver use gpio_matrix to connect pins.