How to send something through UART on ESP32 DEVKIT

[soibac35]

Hello,

I have looked around the forum but there no question on ESP32 DEVKIT uart. I want to have a simple application that will send AT command to another board from ESP32 DEVKIT and read whatever the other board response.

I flashed esp32-20190125-v1.10.bin firmware. There are no uasyncio and I am unsure what library UART from machine has. Do we have a way to check it ?

I wrote an independent program to test UART

Code: Select all

uart = UART(2, baudrate=9600 )
uart.init(bits=8, parity=None, stop=1)
time.sleep(2)

uart.write('print(1+2)\r\n')

uart.read()

and output show UART already NULL

I (401) cpu_start: Pro cpu up.

I (401) cpu_start: Single core mode

I (401) heap_init: Initializing. RAM available for dynamic allocation:

I (404) heap_init: At 3FFAE6E0 len 00001920 (6 KiB): DRAM

I (410) heap_init: At 3FFC0E38 len 0001F1C8 (124 KiB): DRAM

I (417) heap_init: At 3FFE0440 len 00003BC0 (14 KiB): D/IRAM

I (423) heap_init: At 3FFE4350 len 0001BCB0 (111 KiB): D/IRAM

I (429) heap_init: At 400915EC len 0000EA14 (58 KiB): IRAM

I (436) cpu_start: Pro cpu start user code

I (6) cpu_start: Starting scheduler on PRO CPU.

I (90) uart: ALREADY NULL