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esp-03 modules, no uart comms no matter what

PostPosted: Tue Oct 20, 2015 1:22 pm
by tonyg80
hi,

i have finally got round to attempting to play with my esp modules.
i have a pair of esp 03 modules and after spending the better part of the last few hours going through this site and many many different things to try from google im stumped.

i have an ftdi adapter that definately works and i can chuck it straight on my microchip pic and send/recieve serial data no problem so i know that is fine.

i have tried my modules as specced by others success with them by having my connections :

gnd - gnd
vcc - 3.3v ( 1A capable )
ch_pd to vcc via 2.2k res
gpio 0 - gnd
gpio 15- gnd
ftdi tx - esp rx
ftdi rx - esp tx

i have set my ftdi to 9600 and 115200 as well as swapping my tx/rx lines and even trying gpio2 to vcc as some have stated is needed but regardless i get absolutely nothing at all,i cant even get the uart to connect to flash it in any way

my soldering of the wire to each pad is good and clean with a solid connection to each pin used but i am getting knowwhere and its just becoming so frustrating as their seems to be so much contradicting information at times for the same module that it just gets ridiculous.

i bought these from an ebay sellr survy, so either they do not come flashed and i cant get them to even connect or that seller may be selling a few bricked ones but so far i have not found anyone saying they have used that seller and they dont work.

so im stuck good now, i cant flash it, i cant connect it and now i need to find some at commands to try but honestly if the uart wont even connect then im not really holding my breath on that one.


well i finally ended up calling it quits on this for the night at about 4am, i even had gpio 16 pulled hi/low / sideways as some posts i gfind on the net seem to say that needs to be pulled high.

so im stuck with modules that dont even seem to connect to the uart so what now? id like to try a few more things if others have ideas before i commission these things to the garbage, seems to be too many issues with these just for trying to communicate with it


tony

Re: esp-03 modules, no uart comms no matter what

PostPosted: Tue Oct 20, 2015 1:29 pm
by Barnabybear
Hi, just a quick ones to start - have you got your ftdi ground to the ESP ground?
Pull GPIO 2 high with anything between 1K & 10K (it needs not to be low).
GPIO 0 will need to be high aswell after the flash.

Re: esp-03 modules, no uart comms no matter what

PostPosted: Tue Oct 20, 2015 2:03 pm
by tonyg80
hi barnabybear,

thanks for the info, anything is helpfull it seems for these lol.

im just going to desolder the wires attached and put some beefier chopped component legs in their place so i can plug it into the breadboard just in case one of the wires may not have been making contact correctly, its worth a shot sometimes the simple things make the difference.

the esp gnd is tied to the psu gnd on the breadboard along with the ftdi gnd so they are electrically referenced to each other, im hoping it was just those silly wires but hopefully get a definitive answer to that shortly, ill post back once the wires to leg swap has been done.


tony

Re: esp-03 modules, no uart comms no matter what

PostPosted: Tue Oct 20, 2015 3:31 pm
by tonyg80
well it appears that i may have managed to flash my module, after desoldering the mass of flying leads and replacing them each with snipped off resistor legs and pullup/pulldown resistors and about 1500uf on power input lol.

VCC to VCC
GND to GND
CH_PD to VCC via pullup r
GPIO15 to VCC via pullup r ( i have randomly seen people posting this does or does not need to be pulled up)
GPIO02 to VCC via pullup r
GPIO00 to GND via pulldown r
GPIO15 to GND via pulldown r

throughout this experience two things come to mind,

it seems that my esp 03 modules with their 512k flash are often referenced to as older designs when discussed, does this mean their are many different pinout variants for this specific model?

the bare minimum pin connections needed for either flashing or normal run seem to also be greatly varied through all the available info and it seems that their is often no discernable 100% only these pins for flash versus only these for normal operation.

is their 100 % correct info for each of the modules that is not a gathering of all the different methods people have had to use to get their devices to operate correctly either way as otherwise it is extremely confusing to try and initially get started when everything one could easily find over a couple of hours just causes more confusion.


tony