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Baud rate for ESP8266-201?

PostPosted: Fri Jun 26, 2015 11:44 am
by HermannSW
Hi,

received new ESP8266-01 today.
With Arduino Serial monitor I can see messages after resetting, but all junk, for all baud rates.

Since under Linux minicom does not easily allow for different baud rates I did connect:
Code: Select allESP8266-201            USB2UART
3.3V                   VC
RX                     TXD
TX                     RXD
GND                    GND
IO15 (GPIO15) ->GND
CHP_EX -> 3.3V
RST -> GND


With RST at GND a restart should go to flash mode.

For all B in {2400, 4800, 9600, 19200, 28800, 38400, 57600, 76800, 115200, 230400} I did:
* press UART reset pin
* esptool.py --baud B flash_id

No success -- which baud rate should I choose?

(blue LEDs of USB2UART as well as ESP8266-201 blink in sync several times when executing command)
Image

Hermann.

Re: Baud rate for ESP8266-201?

PostPosted: Fri Jun 26, 2015 12:52 pm
by cal
The odd baud rate is 74880 baud.
Some usb uart adapters don't support it and use e.g. 9600 baud instead.
If your 9600 baud garbage looks the same as 74880 it does not support it.
But the flash code should use auto baud setting on esp side AFAIK.

Cal

Re: Baud rate for ESP8266-201?

PostPosted: Fri Jun 26, 2015 1:00 pm
by Stoney
I saw your post in the other thread.
why not try installing the esp8266 arduino lib and use that to program with, I have been playing with ESP's for a few weeks and have not yet touched pytool. Even if it is just for a test and make sure all is well.
I use nodeMCU's flasher if I need to flash a bin, I have tried modemcu and frankenstion but the arduino lib is more understandable to me.
I have never had to set 76800 baud at any time unless it was just to look at the boot message to check it out.

Another problem is likely power, out of the box the ESP seem to all start an access point, this needs 200-300mA
your usb converter is only good for 50mA.
generally you will see it start up and then die horribly and drop USB though..

Re: Baud rate for ESP8266-201?

PostPosted: Fri Jun 26, 2015 2:29 pm
by HermannSW
Thanks,

I tried 74880 with esptool -- did not work.

Then I tried to flash Blink demo with Arduino ESP IDE, did not work with all selectable baud rates.

I found the ESP AP and connected to it getting IP address 192.168.4.100.
Ping 192.168.4.1 worked fine.

For some reason I do not see the garbage after reset in Arduino IDE Serial monitor anymore at any baud rate, neither with RST->GND nor with RST->3.3V after reset, so I cannot tell wether 9600 garbage is the same as 74880 garbage.

I am feeling locked out of my new ESP ...

Is my cabling OK?

Hermann.