ESP8266 Community Forum

- Mon Jul 04, 2016 8:20 am #50162 Hi,

Something still unclear to me!!!

I currently use ESP12E as a single chip and I need 3 GPIOS (2 as OUTPUTS and 1 as INPUT).
I configured GPIO4 and GPIO5 as OUTPUTS as it seems they are not linked to any other function ...
BUT I don't know which one to use as INPUT!
I tried to use GPIO9, GPIO12 with the following line:

Code: Select allpinMode(9, INPUT);

but the Soc does not boot up
According to the picture below, some GPIOs are used for SPI, UART ...
Suppose I'm not using SPI, how can I reassign a SPI pin to a simple GPIO???
I'm afraid I'm completely lost with the way I can use GPIOs!

- Mon Jul 04, 2016 11:40 am #50171 Don't use GPIO6-11 as they are used for the flash chip that holds the code. Only use the ports on the two sides.

- Mon Jul 04, 2016 12:25 pm #50177 Also, make sure your have RES/CH_PD pulled up, GPIO15 pulled down, and also GPIO2/GPIO0 pulled up.

- Mon Jul 04, 2016 4:13 pm #50198

Don't use GPIO6-11 as they are used for the flash chip that holds the code. Only use the ports on the two sides.

Hi rudy,
I also tried with GPIO12 which is out of your "not to use" range but I have the same behaviour.
However I don't understand what is the aim of 12E version if I can't use the extra pins ...
Moreover, I read that if flash was in DIO mode and not QIO it would be possible to use GPIO9 and GPIO10, but I don"t know how ...