ESP8266 Community Forum

- Sun Jan 18, 2015 7:03 am #7601 What custom firmware do you using?
You can use RXD as GPIO pin, at boot time this pin doesn't output any signal so it can drive relay.

- Sun Jan 18, 2015 7:24 am #7604 Wow great didn't know that! At least 1 relay
I'm using nodemcu-firmware

- Sun Jan 18, 2015 8:05 am #7607 Hey,

Can you guys help me? I have the same problem but on a different config.

1) I also have a 5V 2A max main power supply (or directly to a USB port)
2) my voltage regulator is a LM3940 for which i have a 100uF cap between the 3.3V and GND.
3) CH_PD to 3.3V directly
4) 3.3V connected to a LED through a 1k resistor and then connected to the RX pin. (also tried with this disconnected)
5) TX pin connected to FTDI

I tried pulling up the GPIO0 pin to vcc through a 10k Resistor like you suggested but it still requires a few powers or a reset to boot up.


Should I just use another voltage regulator? Are any other pins that should be pulled (up or down)?

- Sun Jan 18, 2015 8:53 am #7612

Hey,

Can you guys help me? I have the same problem but on a different config.

1) I also have a 5V 2A max main power supply (or directly to a USB port)
2) my voltage regulator is a LM3940 for which i have a 100uF cap between the 3.3V and GND.
3) CH_PD to 3.3V directly
4) 3.3V connected to a LED through a 1k resistor and then connected to the RX pin. (also tried with this disconnected)
5) TX pin connected to FTDI

I tried pulling up the GPIO0 pin to vcc through a 10k Resistor like you suggested but it still requires a few powers or a reset to boot up.


Should I just use another voltage regulator? Are any other pins that should be pulled (up or down)?

Hi!
Few questions for you:
1) have you tested the voltage between vcc and gnd pins of esp8266? It's 3.3v and stay 3.3v also when the board doesn't boot?
2) what's firmware are you using?
3) have you tried to connect CH_PD to 3.3v through a 10k resistor?
4) are you sure that your power supply (5v 2a) it's not fault?
5) have you tried to leave tx and RX floating and check if you can find the esp8266 WiFi network with your PC or smartphone? You must set AP mode on esp8266 before disconnect the RX and TX