ESP8266 Community Forum

- Wed Sep 30, 2015 6:18 pm #30214 I encountered a weird problem after flashing the newest version :

I upgraded the firmware to the newest one : AT version : 0.50.0.0 and sdk : 1.4.0, then I issue commands in order to check its operation and everything works fine. Then I power-cycle the module (i.e turning it off and on again) and the ESP stop responding to any command with any bdr!

what can be the problem and how can I solve it ?
thanks!

- Wed Sep 30, 2015 8:01 pm #30219 Did you put back both GPIO2/GPIO0 to VCC thru PullUps ?
Many people forget that after finish to upload new firmware.

- Thu Oct 01, 2015 2:24 am #30244 Sure!
When i flashed it , i put gpio0 to gnd and gpio2 to vcc and when it finished been flashed i put gpio0 to vcc and leaved gpio2 connected to vcc for the normal operation mode as described in the manual.

Note that the esp is working after flashing with the new version but only for a one power cycle. Means that when i turned it off and on for the second time it stop responding.

Maybe its because of the lack of pull ups ? Why should i need to connect it through pull ups ? Why not directly ? With what size of resistors ?

- Thu Oct 01, 2015 8:22 am #30259 The symptom you've described is normally happened when GPIO0 is left to GND, since at second power cycle, it bring ESP back in programming mode. But since you said that you setup GPIO0 properly, (although without pullup, it is not mandatory, but a best practice since GPIOs can becomes an output and can introduce shorts when no pullups present), it should not behave like that.
Maybe you should describe here your other connections, RST, CH_PD with PullUps, and GPIO15 with PullDown.