Nonstandard UART speed
Posted: Tue Nov 29, 2016 8:32 pm
I designed an environmental sensor with an ESP8285 chip. After having assembled it, I wanted to test it with AT commands. I received some sort of signal, but with frame error after pushing the reset button. But my AT commands were unanswered. I checked the initial TX signal with an oscilloscope. It looked ok, but had a baud rate around 7519. What I checked:
Oscilloscope photo: http://imgbox.com/KsjlgkGK
Project topic: http://www.esp8266.com/viewtopic.php?f=11&t=12147&p=57182
- The crystal: It provided a 26Mhz sine wave (as intended)
- The 12k resistor: It had less than 1% value error, and I measure 0.6V on it.
Oscilloscope photo: http://imgbox.com/KsjlgkGK
Project topic: http://www.esp8266.com/viewtopic.php?f=11&t=12147&p=57182