ESP8266 Community Forum

- Wed Dec 03, 2014 8:49 am #3920 Hello everyone. I have this chip and I have been working with it for a few hours now to no avail. I was wondering if anyone could spread some insight.

I am using a USB to rs232 serial adapter and between that and the esp chip I have a max232 chip and two voltage dividers on the transmit and receive lines. I also am using a separate 3.3v supply. I have used this serial setup on numerous other occasions and haven't had any issues.

I pulled up and pulled down the pins that you guys are suggesting as well as tried every baud rate imaginable. I cannot get the device to respond to any AT commands and every time I put it into "bootloader mode" I get a "failed to connect" message by the flash downloader.

The only response I have gotten out of it, is by putting it into"bootloader mode" with the terminal still open. When I do that I get a bunch of scrambled bytes back that no baud rate seems to match up with.

Help please?

- Thu Dec 04, 2014 10:44 am #3971 with GPIO0 left open (no connection), do you see data on serial terminal on power up?

and for your voltage dividers, tx of esp to rx of max232 doesn't need to have voltage divider.

- Thu Dec 04, 2014 11:20 am #3973 I see nothing during power up. I have a few modules so I have tried one with voltage dividers and one without- nothing from either...
edit- with a logic analyzer hooked up I am seeing something but it's all scattered:
http://imgur.com/fl0Vcvg

- Fri Dec 05, 2014 2:51 am #4030 In all likelihood, that is the bootloader output - this module outputs some info at 74880 baud before it switches to 9600. There is an option in the Saleae serial analyzer settings to use baudrate auto detection (don't remember the exact name).