Serial USB TTL Communication Problems (Newbe Question)

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Re: Serial USB TTL Communication Problems (Newbe Question)

By haroldjclements
- Tue Dec 09, 2014 11:13 am #4390 Yea, sorry, my description was probably ambiguous.

At the point of power on the TTL is connected with the terminal window open waiting with bated breath for signal from the ESP.

Thanks again,
Harold Clements
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Re: Serial USB TTL Communication Problems (Newbe Question)

By gerardwr
- Tue Dec 09, 2014 11:20 am #4391
haroldjclements wrote:This is what I get when powering on (without the resistor between RST and GPIO0):

1. The RED power LED is lit and remains constant.
2. Immediately after power-on, the BLUE LED flashes a few times. At this point (power on), I am connected to a the Serial TTL (as descried in my previous posts and have used both "Terminal" by b@ray and the more basic Arduino serial viewer. I get nothing (not even "jibberish" in the terminal).
3. I do not see any prompt ("ready" or ">") .


alonewolfx2 is right, the prompt of the AT firmware is "ready", sorry for the confusion.

Hmmmmmmm….. The blue LED blinks, but NOTHING in the terminal?!

Are you ABSOLUTELY sure that you have not swapped the send and receive lines. I saw in your opening-post that you "crossed" RX and TX, that is indeed the way to do it.

- What are using on your PC as TTL-serial interface?
- When you "loosely" connect the serial-receive line of your PC to Vcc, do you see any "jibberish" in your terminal emulator?
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Re: Serial USB TTL Communication Problems (Newbe Question)

By haroldjclements
- Tue Dec 09, 2014 11:49 am #4394 Thank you once more for your reply,

Yea, I have plug and unplugged the RX and TX lines whilst testing and swapping out serial interfaces. I am sure that they are crossed (RX to TX, TX to RX).
I am have tried with both a CP2102 USB to UART TTL and an Arduino Uno (with the AVR removed as suggested in early parts of this chain; although that has not been necessary).

Thank you once more...
Harold Clements
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