ESP8266 Community Forum

- Sun Mar 29, 2015 9:00 am #12925 Hi All,

Please help me out, I just spend three days getting this to work, and am out of options.

What works:
- connect with serial > USB and send commands with a terminal
- Flash the latest firmware

so far so good, but I can NOT connect with my arduino Mega. I have connected with:

VCC & CH_PD 3.3V
RX > RX and TX > TX (and reversed)
GND from Arduino and/or external powersupply / common ground through a breadboard.
Several sketches from the net.

- a 5 V > 3,3 volt shifter,
- same setup with an external power adapter with and without common ground
- directly on the 3.3V of the Arduino
- put a zener diode between GND and TX line (read that somewhere)
- switched RX and TX lines
- put 3,3V on GPIO0

Result = nada. Have tried 9600 / 115200 baud. 115200 works fine when connected with USB>serial adapter.

Where do I go wrong?

- Tue Mar 31, 2015 2:57 am #13094 I believe I am in the same boat as you too. I was able to get the PC USB->Serial connection working with the ESP8266. I also noticed that the ESP8266 was getting heated up with the 5V PC USB -> Serial connection.

I haven't been able to work with the 3.3V supply. The way I created the 3.3V is to use a resistor divider from the PC USB output (not the Arduino 3.3V output directly). However, the current that I get from this connection is only about 0.8 mA. The ESP8266 module requires about 300mA I believe. I plan to integrate an LDO that will help in providing the required current.

- Sun Apr 12, 2015 9:53 am #14284 I know this problem was mostly solved, but I had one thing to add.

I know it is obvious, but I spent 2 days trying to get different terminal apps to connect and send/receive commands from this thing and in the end my only problem was my CR+LF settings. The odd thing is that it doesnt want the same settings every time (go figure... this module is cool but insanely inconsistent. For me at least). So each time i dont get a response I mess with those settings and bam, it works.

Just a tip for others who had my issue so you don't waste too much time for something so simple.

- Tue Oct 06, 2015 2:30 am #30633 i got problem when i am checking AT command with putty.
always it returns the operator">" or ">>".
i do not know whats going wrong with it, i was reverse the RX and TX pin but its not working.

AT
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