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Re: Bricked LA40C650. Pls help!

Posted: Fri Dec 23, 2011 8:26 am
by juusso
emm... seems i confused my self and confused you too... Sorry. Misunderstood the situation. DB15 is normal VGA socket... :oops:
you`re right. Sorry once again.

Then where is the problem? If you use working ttl cable (checked? i mean if connect tx and rx of cable do you get echo of symbols you input?), then it should work with 4,11,5 pins connected.
Note that rx of cable should be connected to tx of tv.

Is your cable ok?

Re: Bricked LA40C650. Pls help!

Posted: Fri Dec 23, 2011 1:48 pm
by juusso
Please dont paint those schematics of cable...
You should know, cable lenght is important - better dont use any additional cables. Use your USB ttl cable and connect it to TV`s VGA port, avoid long distances.
Use Laptop or take TV closer to PC.

And finally, i think you should swap tx and rx.

TV`s rx(pin4) - cable`s tx
TV`s tx(pin11) - cable`s rx .
GND is ok.

Don`t be scared to experiment with pins. Also we don`t know if cable helps - if you havent set rs232 do debug, cable is useless.

Re: Bricked LA40C650. Pls help!

Posted: Sun Dec 25, 2011 4:25 pm
by nspierbundel
Before you talked about 3.3v
Do you have 3.3v or 5v or both?
The max chip could be in your prolific. Check if cable settin is ttl 3.3v maybe jumper if it has both
With a non ttl connection it will not work.
Daniel

Re: Bricked LA40C650. Pls help!

Posted: Mon Dec 26, 2011 8:29 am
by juusso
If you haven't set rs232 to debug in service menu before to brick, then all what you see in terminal is black screen without any symbols on it and no input. If you checked your cable by making short connection between rx and tx and you got it working, then I think problem isn't at cable side, but TV's. Somehow you haven't said you checked cable. Did you?

Re: Bricked LA40C650. Pls help!

Posted: Mon Dec 26, 2011 10:35 am
by juusso
Yes, eeprom reset is the solution to get to service menu, make factory reset, set rs232 to debug and watchdog off.

I can't check your taken photos, I'm on smartphone right now. Just at evening maybe...

Check forum for similar eu models and try procedure as described. I think eeprom must be same as yours...