ESP8266 Community Forum

- Fri Feb 15, 2019 10:56 am #80575 Hi guys..

New to all this ESP stuff, trying to figure out what is the freaking difference between those 2 chips in the photos.





Let me try to explain.. The right one with the blue led can be flashed normally and works fine with Tasmota and ESPEasy, flash, and boom all good.
The bastard on the left I've tried to flash with every possible version of Tasmota and ESPEasy.. It simply doens't work.. The only way that I could access it was with minimal OTA version from ESPEasy, but then I can't upgrade from there. I also can't run AT commands using the COM or anything like that..
I've got 3 of each model and the same happen for every chip. I'm going crazy testing everything possible with no good results.
Flashing using esptool with linux.

Does anyone has any idea of what could be happening?

Thank you

- Sat Feb 16, 2019 6:03 am #80583 the left one with red led on might be from the 1st generation with small flash (512k) and none of the needed pull-up/down resistors.

- Mon Feb 18, 2019 7:31 am #80630 After a lot of testing, I found how to make both work equally. Still not sure the main difference thought.
They are both 1024k but the on in the left requires an extra power cable connected to the 3rd pin to boot.

The on in the right works fine only with one 3.3v.

Thanks.

- Tue Feb 19, 2019 2:36 am #80654 as I allready mentioned: there are some pull-up / -down resistrors needed (highly recommended, best practise) for stable operation:
pull-up: rst, gpio0, gpio2, en
pull-down: gpio15

as gpio15 is not available on the 10pin connector, all ESP-01 boards have the necessary pull-down.
the others - EXCEPT EN - are "optional" meaning: internal pull-ups (as weak as they may be) can be sufficient for most scenario - I would not trust in them and apply "best practise".