ESP8266 Community Forum

- Tue Dec 09, 2014 1:40 am #4331 I do not have an oscilloscope to confirm. However, I believe the gpio pins are flickering when I'm not changing their states with gpio.write().
It seems to affect both gpio.HIGH and gpio.LOW. Both states flicker. This behavior is on all GPIO pins, not just some of them.
While this is only annoying on an individual output LED. It would be disastrous on SPI.

Hopefully this is just user error and not something inherent to NodeMCU because I really like NodeMCU.

- Tue Dec 09, 2014 5:15 am #4342 flicker confirmed, I have a oscilloscope.

after some tests, I believe it's from the power consumption of wifi transceiver.

test 1, nodemcu firmware running, do nothing, flickers shows in gpio.
test 2, when burning firmware in uart. no flickers.
test 3, re-compile sdk, without lua interpreter(nodemcu), flickers shows.
test 4, nodemcu firmware running, switch STATION mode to SOFTAP mode, more flickers show.
test 5, nodemcu firmware running, config station mode with wrong ssid/pwd, more flickers show.

test 6, could someone with oscilloscope test the AT firmware?

- Tue Dec 09, 2014 6:27 am #4348 i dont have oscilloscope but i tried at firmware and it have flickers.
i tried nodemcu, it have flickers
EDİTED: i tried freertos and it seems stable more than other firmwares
i tried nodemcu with gpio3 as output it have flickers.

i am not engineer. can we use small capacitor like 0.1 microfarad on the output pins? maybe it work without flickers.

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- Tue Dec 09, 2014 9:15 am #4366 zeroday, thanks for all that work with the scope.
alonewolfx2, thanks for the confirm and info about freertos. Another firmware for me to play with!