Missing Digital Pins?

Hi There!

I am using ESP12F as a standalone. It has 8 usable gpio pins(4, 5, 9,10,12,13,14,16), but on the blynk app, gpio 9,10 are not listed. Am I missing something here?

Sorry I’m not in a place where I can look this up easily but I believe GPIOs 9 and 10 communicate with the flash chip in some way. Using these pins would affect how the ESP8266 sends/receives data from the flash chip.

i use GPIO 2 as well… as in/out but don’t use 9/10 as these are supposed to be comms only (whereas 2 seems to be comms & GPIO)

Thank you all for your responses and clarification.

@Dave1829, Can you please let me know how to use GPIO 2 as a output pin? As per the my understanding, GPIO 0& GPIO 2 needs to be pulled HIGH and GPIO 15 needs to be pulled LOW for the normal operation and this is how I wired my circuit.

i don’t know how i just know that i do use it.

i switch a relay on off with my GPIO2

when i am uploading new sketch to it, the relay light blinks,

to operate my ESP12E i have:

that’s it!

lots of people talk about pulling “this and that up and down” - meh, i have no issues so far…

here is what the maker shows:

Ok… I have ESP12-F. I tried to boot without pulling GPIO2 HIGH without success. Also what I noticed is, below requirement is only for flash boot. Once the module is booted these GPIO’s can be used.

GPIO0 - HIGH (LOW for UART download mode)

i don’t know what “flash boot” means?

@Lavan yes there are several pins that need to be high or low for flashing and high and low for running mode. But once the flash is done or the device is running you can use the pins as you like. 9 and 10 are very special though and their is a github thread how you change the flash settings to be able to use pin 9 but not normally pin 10.

It means… module boots from SPI flash

Guys - so are we missing some digital pins or not? ))

@vshymanskyy if users change from the faster QIO to the slower DIO it may be possible to use GPIO 9 and GPIO 10, with or without hardware modifications. I think some ESP versions now offer access to 9 and 10 as standard.

This is a recent github discussion relating to gpio pins 6 to 11 https://github.com/esp8266/Arduino/issues/2124#issuecomment-225165858

Might be worth adding 9 and 10 for all ESP variants and then it would be up to the user if they want / need to carry out any mods to be able to use them.

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@Costas, 10x! I’ll add those pins.