ESP8266 Community Forum

- Mon Oct 06, 2014 10:27 pm #1351 I bought a couple modules and I'm wondering if I'm doing something wrong or fried something along the way.

I'm just trying to get a basic serial connection to my computer so I can test out AT commands. I'm using an Arduino Duemilanove and have connected the module directly to the Arduino as shown in this post: http://zeflo.com/2014/esp8266-weather-display/

All I have on the Arduino is the "Bare Minimum" sketch, so I could just use the FTDI chip to talk to the ESP8266.

When I have the jumper going from VCC to CH_PD, the blue LED flashes quickly, along with the RX and TX lights on the Arduino and my computer plays the "Device Disconnected" sound. When I disconnect the jumper, the flashing stops. Another post suggested using a 10K resistor between the VCC pin and the CH_PD pin, though the same thing happens.

When I have the jumper going to the CH_PD pin disconnected, just having the four wires directly connected to the Arduino, I can launch the serial monitor and attempt to send commands, though I get no response. When I send a command, I do see the blue LED flash momentarily.

Is there anything else I should test?

- Tue Oct 07, 2014 12:00 am #1352 Please check the numerous posts regarding the module wiring in this forum or on Electrodragon's wiki page: basically, you need to tie GPIO0 to either VCC or GND if you want a normal or upgrade boot.

- Tue Oct 07, 2014 11:06 pm #1405 Thanks for pointing out the Wiki, I must have missed that when googling around last night. I do apologize for asking a question that appear to have answers elsewhere on the forum, though I just can't seem to get the modules working and there seems to be some conflicting information about these modules spread around various blogs and websites.

I did a couple more tests without any luck. First, I followed the First Time Use Guide which was essentially what I was doing the other night, though again I didn't get any replies after sending an AT command in the Arduino Serial Monitor, PuTTY or SSCOM32. I also tried pulling the GPIO0 pin both high and low, though still didn't get any sort of output.

I do have a logic level converter and hooked it up like so: https://dlnmh9ip6v2uc.cloudfront.net/as ... 8b4567.png
However, the module's power LED doesn't light up, so that example may not be applicable for this case. I'm going off of my crappy memory, though when I measured the voltage across the two center, right pins (Connected to power and ground pins of module on the right), I didn't get more than a couple volts.

The only things I haven't tried thus far is using an external 3.3v power supply, which would require some digging around the house to find something. The second thing is the resistor method of dropping the serial logic level down. However, I've seen a couple examples just driving the module directly from an Arduino, so in my mind it should work...

Sorry for rambling, though these little modules are driving me nuts. I'm very excited to start playing around with them and start a couple projects, though I'm just not getting anything out of them!

- Wed Oct 08, 2014 12:00 am #1408 You need to drive GPIO0 and CH_PD at least, best is to tie all 4 central pins to +3.3V.