ESP8266-01 and Arduino UNO not working with logic level shifter

Thread Starter


Joined Nov 29, 2015
Hey. I am working with ESPS and trying to program them with Arduino UNO with arduino software. I am able to write a program to ESP8266-01 without using any logic shifting - I connect RX to RX and TX to TX directly. When i ground the reset pin while reset the GPI0 i can write the program to ESP8266 but it does not seem to do what it is supposed to.

The code I have used:
ESP8266 Blink by Simon Peter
Blink the blue LED on the ESP-01 module
This example code is in the public domain

The blue LED on the ESP-01 module is connected to GPIO1
(which is also the TXD pin; so we cannot use Serial.print() at the same time)

Note that this sketch uses LED_BUILTIN to find the pin with the internal LED

void setup() {
pinMode(LED_BUILTIN, OUTPUT); // Initialize the LED_BUILTIN pin as an output

// the loop function runs over and over again forever
void loop() {
digitalWrite(LED_BUILTIN, LOW); // Turn the LED on (Note that LOW is the voltage level
// but actually the LED is on; this is because
// it is active low on the ESP-01)
delay(1000); // Wait for a second
digitalWrite(LED_BUILTIN, HIGH); // Turn the LED off by making the voltage HIGH
delay(2000); // Wait for two seconds (to demonstrate the active low LED)

This program should flash an inbuilt BLUE led, but is not doing anything. However the blue LED flashed rapidly when the ESP8266 is being programmed.

When i try to use logic level shifter that I have bought for the purpose the program the ESP8266-01 with arduino, is not working. I am just getting usual memory error:

warning: espcomm_sync failed
error: espcomm_open failed
error: espcomm_upload_mem failed
error: espcomm_upload_mem failed