ESP32 Forum

Hello,

I wanted a clarification regarding pinouts for ESP32-DevKitC-VE. Can I use the TX & RX pins ( As marked on https://docs.espressif.com/projects/esp ... vkitc.html) as outputs (with internal pullups) ?
Any disadvantage of doing the same ?

I read that Pins 16&17 would be for internal use for PSRAM. The amount of PSRAM is 4 MB ? or 8MB ?


Thanks

You could refer to the datasheet for GPIO details, user guide clearly shows which GPIO is for every pin.
You could use TX and RX but they are default UART0 port, so they will output some logs at power-up, generally, we suggest you not to use them.
PSRAM is 8 MB.

Actually I we designed the product using your base 4 MB Wroom module and later we are looking at WROVER modules. The pins 16 & 17 were already used as per our previous design and now after going through the documents again we found 16&17 cannot be used as they are linked to PSRAM.

I am planning to attach only 1 led and 1 button to these ports. Just wanted to be clear that it will not lead to a problem after we design the remaining product.

@ESP_LJH
Thanks !

Just one more clarification which I cant find in any documentation. If I use Flash encryption in release mode and UART is disabled, will the pin also be disabled or can I still use it for Output?

Thanks once again !

Flash encryption won't affect the UART. (Although do note that secureboot, which is usually used with flash encryption, may disable UART download mode, so you won't be able to upload new code using that uart anymore.)

@ESP_Sprite
Thanks for the reply... but what I really wanted ask was if I use the GPIO 1 (TX Pin) as an output pin, will the GPIO1 also get disabled with secure-boot ? (Meaning if it is set as output, will it stop working as the UART gets disabled) ?

[UPDATE after Code Testing]

GPIO 1 cannot be used alongwith serial monitor (UART) / USB with ESP DevKits. Using GPIO 1 with serial monitor(through USB) will cause Core to Panic / Crash.

Thanks to ESP_LJH and ESP_Sprite for their help and support!