ESP8266 Community Forum

- Sat Jan 28, 2017 1:36 pm #61661 Hi

I'm using the esp-12f with the white mounting board. I'm making the PCBs for the esp myself. I also have a little programmer board, on which I put the white mounting board with the esp to flash it. The programming board has a 10k on gpio0, a 10k on gpio2, a 10k on res, a push button on reset and a push button on gpio0 for programming. I have an external power supply with a lm1117t that supplies the 3.3v (with 2 capacitors 10u on both sides of the lm1117t). The white mounting itself has the ch_pd pulled up and the gpio15 pulled down.

Now my problem. When I use the ESP on my self etched pcb (with some relays on it etc...) everything works perfectly fine, no resets at all.
But when I put it on my programming board, I barely get a readable output over the serial interface. Sometimes it boots up normally, but most of time it puts out garbage.
When I start the programming mode (reset and gpio pulled down) I can flash the esp without any problem! But after the restart I get these weird problems. Also after pressing reset severeal times it doesn't get better. If I pull out the ESP and put it on my etched pcb board everything works fine.
The serial interface is connected over a usb2ttl converter which is set to 3.3v.

Do I need additional capacitors or resistors anywhere or am I missing something for the serial interface ?

thanks
regards
Erich

- Sat Jan 28, 2017 2:36 pm #61662 Could you post a picture of the setup using the programming board?

- Sat Jan 28, 2017 3:20 pm #61666 Hi
This is the version on my breadboard. I also made a etched version of it before, but it had the same problems.

Regards
Erich

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- Sat Jan 28, 2017 6:29 pm #61675 Move the 3.3 volt regulator as close to the esp module as possible. Put a 100 - 470uF capacitor across VCC as close as you can fit it. Put a capacitor 10 - 100uf on the input of the voltage regulator.

Take a look at this thread. I have a picture of one of my modules on a breakout board like you use. I have a 3.3v regulator soldered to the bottom of the board. On the first page of this thread I wrote some stuff that is worth a read.

One more thing I would include is a small capacitor from the reset line to ground. Just to prevent a noise glitch disrupting the module.

Let me know how you make out.