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By Motzl
#126996
@ Talada. I had the same Problem and it was really frustrating. Your sketch worked for me, thanks a lot!
By eboucher
#133934
after reading what i would assume is all of hte posts on this topic, and trying all of the code posted i am still at a loss. i have the serlcd v2.5 and made the rookie mistake of leaving the tx line hooked up while i programmed my arduino mega. needless to say i am stuck with a dimmed display, and a row of boxes on line 1, as stated previously i have tried to run everyones code to reset the screen to no avail. any suggestions as to what i may be doing wrong?
edit: found an article on another forum and i have found out that it just an uninitialized screen, but again after trying i cant get it to reset. would it be wise to not use the serial connection and set it up for parallel? and bypass the chip?
By ViennaMike
#138373
@Taleda. My thanks also! I lost use of the LCD when trying to adjust the brightness (since saw that at a delay is required to avoid this. Your code fixed it, and I've saved it in my Arduino sketch files to have handy should I need it again.
By JobCreator
#143596
I'm having similar problems, and the recovery programs listed here aren't working - though I do get a "Reset to 9600 baud" message, leading me to believe the LCD isn't dead. I'd really like code that runs on the Basic Stamp 2, if possible - but I'd really just like to get my LCD back.
By d3v4n5
#160833
Hi All,

I know this is an old thread, but hoping someone has some tips.

I decided to start dabbling with arduino, and just received my pro mini the other day. I dug out my serLCD (3.3v), which was working properly with a ubw32. However, the screen stubbornly remains blank no matter what I try. I thought I may be on to something when I read the issue with leaving it plugged in during programming the mini. But neither of the suggested resets seem to work.

Could anyone verify if this is the correct reset code?

(from rst26508, post #6)
Code: Select all
void resetLCD() { 
  Serial.write(0x07); 
  Serial.write(18); 
  delay(10)
}
(from Talada, post #10)
Code: Select all
void lcdReset(){ 
  Serial.write(0xFE);
  Serial.write(0x72);
  delay(10)
}
(my own version of rst26508's, using the 7C command flag)
Code: Select all
void lcdReset(){ 
  Serial.write(0x7C);
  Serial.write(18);
  delay(10)
}
( I've modified the Serial.print( _x__, BYTE) which the arduino 1.0.5 compiler didn't like to Serial.write(_x__) )

None of these seems to work. What does work is turning on/off the backlight, so I know it's getting something, but there's no splash screen (and trying to toggle doesn't work), and no text at all (even trying to reset the baud).

I've tried all tips found here and the SerLCD url, as well as trying the softserial lcd code. The screen remains blank, no characters at all. I've also verified using the xprotolab uart sniffer (great little board!) that the expected serial is on the line.

If anyone else has had the same issue and has any remaining tips to revive the screen, greatly appreciated! I must admit I'm stuck.
By gggplaya
#194967
@d3v4n5

Did you ever find a fix for this. I'm having the same problem. First I did find that the JST plug is on backwards, so VDD and RX pins were swapped. I fixed that. I can get the splash screen, but no text or anything after that. Just occasional gibberish. I've tried all the reset codes, none of them works. I'm using the example arduino serLCD code, which actually works fine on my 16x2 lcd. But not the 20x4 lcd.