Arduino code communication to HM-TRP RF Module By ESP32
There are three hardware supported serial interfaces on the ESP32 known as UART0, UART1 and UART2. Like all peripherals, the pins for the UARTs can be logically mapped to any of the available pins on the ESP32. However, the UARTs can also have direct access which marginally improves performance. The pin mapping table for this hardware assistance is as follows.
UART RX IO TX IO CTS RTS UART0 GPIO3 GPIO1 N/A N/A UART1 GPIO9 GPIO10 GPIO6 GPIO11 UART2 GPIO16 GPIO17 GPIO8 GPIO7