ESP8266-01 loads from Arduino IDE but doesn't run

Question

I had this working fine a few months ago but can't seem figure out what's changed. I have several ESP-01 and I can upload using Arduino IDE with Generic 8266 board profile but I can't get anything to run. Nothing shows on the Serial Monitor. I've tried simple code like:

void setup() {
  // put your setup code here, to run once:
  delay(1000);
  Serial.begin(115200);
  delay(1000);
  Serial.println("Hello, you've entered setup()...");
}

void loop() {
  // put your main code here, to run repeatedly:
  Serial.println("Good day, you're in loop()...");
  delay(2000);
}

I've tried using a jumper to 3.3v on the ENable pin and a 10k resister. I've removed the GPIO0 after programming. Nothing seems to work. I have 4 chips so I know I'm not doing something.

I have 3.3v on VCC (measured), nothing on RST, EN to VCC (tried 10k to VCC), TX - RX, RX - TX, 0 - Gnd for programming, nothing on 2, Gnd - Gnd

Can you post the bootloader logs? Should get some output at power on at 74880 baud that might help — Dawn Minion

John Smith John Smith · Accepted Answer · 2018-04-30T14:47:25

I found the answer for this problem. It seems that the ESP-01 chip must have 10k resisters on GPIO 0, GPIO 2, and reset to VCC in order function properly. Although the chip seemed to accept the flash, the floating pins were causing problems. Once I added the pullup resisters, it was like magic, everything started working.

ESP8266-01 loads from Arduino IDE but doesn't run

2 Answers