not able to program esp8266

[danny08]

hi guys, i got this esp8266 board https://www.amazon.de/ESP8266-2-4GHz-80 ... wifi+relay .
also, i got this usb to ttl/uart device: https://www.amazon.de/WINGONEER-CP2104- ... s=usb+uart
BUT: im not able to program the esp with espeasy.
i got the right drivers, its recognised as usb to uart device with a com port, i got the right software, and i (think) i got the right program pins.
i connected rx to rx on the usb, tx to tx, and gnd to gnd.
but the sync fails and the board is still the same as before...
i tried many things like switching rx and tx, shortened the two pins in P3, so the device is in bootloader mode.
But everytime it fails so sync and so i cant program it.
what can i do?
For the standard esp8266 there are several ways but on this board i only got this 5 pins, p3 are jumpered, so only 3 left. rx tx gnd, but it wont work..
greetings

[grovkillen]

i connected rx to rx on the usb, tx to tx...

Big mistake. The RX stands for "receiver" and TX for "transmitter"... so you need to connect RX to TX! Otherwise you are transmitting to the transmitter.

[danny08]

..but i switched them sometimes.
even if i connect rx to tx and tx to rx, it doesnt work

[Shardan]

Can't say exactly as i don't have a schematic and the leads on the PCB are covered.

At first: Use a voltmeter and check:
For flashing these values should be given:
GPIO0 = 0 (low)
GPIO15 = 0 (low)
GPIO2 = 1 (high)

Flashing will fail without these settings.

Second: I don't know the programming UART board you use.
As far as i can see from the pictures there is no voltage regulator on that board.
Try to connect the 3,3V on the UART to 3,3V on the board.

Regards
Shardan

[danny08]

my uart board got 3,3v and 5v.
but none of them is connected as there isnt a pin available on the esp8266.
should i program it with power supply connected?
here you can see more pictures https://de.aliexpress.com/item/ESP8266- ... 0c6cac0a52

[grovkillen]

should i program it with power supply connected?.

NEVER have the mains connected when the bare board is exposed!!! Dangerous.

Have you tried the suggested pin states as suggested by Shardan?

[grovkillen]

But if it is only fed through the DC side it is okay. Sorry, didn't see that, but you need to have it with common ground I think. You could have the programmer feed it that way. But you need to see if 5V is enough, just try and see. No harm done if it is fed to little (I think).

[Shardan]

I've seen that pictures but the leads are under the ESP-Chip
so i can't say what is connected to whatever.

There is no pin at the board but there has to be 3,3V as the ESP runs with 3,3V.
You should be able to put a wire on a 3,3V point, maybe on the ESP itself.
Alternatively you may use a separate 3,3V Power supply.

For flashing switch off power, connect the boot jumper (if it is the GPIO0 pin from the ESP)
start the flashing and immediately power on the device.

WARNING:
ALWAYS USE A SEPARATE POWER SUPPLY FOR FLASHING!
We prefer living forum members....

Handling mains voltage isn't everybodies darling.
Even if i'm 20.000 Volts approved and still alive, 70..100 Volts
is enough to kill under bad circumstances.

Regards
Shardan

[Shardan]

i connected rx to rx on the usb, tx to tx...

Big mistake. The RX stands for "receiver" and TX for "transmitter"... so you need to connect RX to TX! Otherwise you are transmitting to the transmitter.

Basically that's right...
but our chinese friends are not too consequent in naming their pinouts.
I've a UART board where the Tx and Rx must be connected Tx-Tx and Rx Rx

[danny08]

one or two times i tried programing it while its connected to a 20v switching power supply.
and not a electrical noob, just more a computer guy which isnt used to work with microcontrollers. thats why i need help, i can only see i have to connect 3 pins and it doenst work
i followed his "guide" https://ucexperiment.wordpress.com/2016 ... ay-module/ and he also has used the 3 pins plus a jumper and it worked, suspicious..

[grovkillen]

You could power it through the original DC in, see the attached picture.

[danny08]

yes its powered with dc. im using 20v. And it works, the standard ai thinker firmware works, but all i want is espeasy. which is pretty funny because with this damn board its pretty hard and annoying.

[grovkillen]

i connected rx to rx on the usb, tx to tx...

Big mistake. The RX stands for "receiver" and TX for "transmitter"... so you need to connect RX to TX! Otherwise you are transmitting to the transmitter.

Basically that's right...
but our chinese friends are not too consequent in naming their pinouts.
I've a UART board where the Tx and Rx must be connected Tx-Tx and Rx Rx

Wow, that is a big puddle of no-no!!! Those darn standards breaker.

[grovkillen]

yes its powered with dc. im using 20v. And it works, the standard ai thinker firmware works, but all i want is espeasy. which is pretty funny because with this damn board its pretty hard and annoying.

But you need common ground I think? Try power it with the programmers 5V.

[danny08]

how do i achieve this?
the DC Input ground comes from the switching power supply, der program gnd comes from usb uart programer

[grovkillen]

Just strip two wires, one for the 5V and one for the GND. Not using a separate power supply. Just the programmer.

[Shardan]

Some general things as far as i can see from the pictures:

There are two voltage regulators on the board.
One is the round coil with the 100 marking and the little chip beside it, an AM2303ADN.
This is a step up / step down converter that converts the input voltage to the relay voltage, usually 5 or 12 volts.
Near the relay there is a little 3-legged chip, a AM1117-3.3. This is a linear voltage regulator, that
goes down from the relay voltage to 3,3V for the ESP.

As Grovkillen says it should be possible to feed 5..28V for the electronics.
A simple standard power supply (wall plug or similliar) should do.
Just do not connect any mains voltage to the relay contacts while progging.

[danny08]

of course. nothing is connected to the relay while im testing, that would be insane.
im only using the dc in for powering the board and the programing pins .

[danny08]

I GOT IT!
With the help of shardan i figured it out.
i needed to connect the power supply AFTER i have started the flashing.
so i connected the usb to uart to the board,ensured that rx goes to tx, started flashing, then connected the power supply and immediately it worked out.

thanks for all your help, you guys are truly amazing.

[grovkillen]

Great! If you could do a step by step instruction here I can add this unit as an "workable esp hardware" for the wiki.

[Shardan]

Great! If you could do a step by step instruction here I can add this unit as an "workable esp hardware" for the wiki.

We really should have some basic flashing howto in the wiki...
The issues and requests about flashing getting more and more...
Hm... Thursday is a holiday here.. if i'll find time i'll give it a try.

[grovkillen]

Great! If you could do a step by step instruction here I can add this unit as an "workable esp hardware" for the wiki.

We really should have some basic flashing howto in the wiki...
The issues and requests about flashing getting more and more...
Hm... Thursday is a holiday here.. if i'll find time i'll give it a try.

Yeah I know... I might also have some ideas regarding a generic flash (using onboard programmer + external programmer). Please start and we'll collaborate a good guide.

[johnnysamu]

I've got it working. I have good pictures. But I can not attach to this forum. It seems all too difficult.

Sorry

[grovkillen]

You can pm me.