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UNO can't communicate with ESP-01 module

PostPosted: Tue Feb 02, 2016 4:12 am
by unicorns4lyf
I have an ESP-01 module connected to the arduino and powered by an external power source. I tried sending AT commands using the serial monitor in Arduino IDE, blue led blinks each time I send a command, but I get no response back.

ESP --- Power
Vcc --- 3.3v
GND --- GND

ESP --- Arduino UNO
GND --- GND
CH_PD --- 3.3v (tied 10kOhm)
RX --- RX (connected 10kOhm to GND and RX Arduino)
TX --- TX

I tried swapping the TX and RX pins, directly connecting the pins without resistors, or even connecting the other pins to either 3.3v or GND like other tutorials schematics. I also tried uploading the BareMinimum code or SoftSerial samples provided by other tutorials. In the end, nothing works.

Also when I try to upload code to the ESP-01 through the IDE I get "warning: espcomm_sync failed error: espcomm_open failed" errors.

Is my module fried or am I doing something wrong?

Re: UNO can't communicate with ESP-01 module

PostPosted: Fri Feb 05, 2016 5:36 am
by vipinchandras
what baud rate are you setting in arduino serial monitor to communicate with esp-01? Try 115200 or 9600.

Re: UNO can't communicate with ESP-01 module

PostPosted: Sat Feb 06, 2016 5:56 am
by vito404
did you look at this instructable http://www.instructables.com/id/Cheap-A ... /?ALLSTEPS

but note that the UNO softwareserial apparently don't like 115200 baud connections

vito

Re: UNO can't communicate with ESP-01 module

PostPosted: Thu Feb 11, 2016 1:15 am
by unicorns4lyf
vipinchandras wrote:what baud rate are you setting in arduino serial monitor to communicate with esp-01? Try 115200 or 9600.



I tried rewiring to get something and 74880 is the only rate that works for me now, the rest just spits out garbled characters. Now when I put CH_PD to HIGH, I get "Fatal exception (0): epc1=0x40217c4c, epc2=0x00000000, epc3=0x00000000, excvaddr=0x00000000, depc=0x00000000"