633 dosent report correct responses


New member
i am using intel board. which is running 64 bit Fedora core 4 and linux kernel version is kernel version.
i have a crystalfontz lcd 633 yyb hooked up to the serial port.
i am able to display characters on line 1 & 2 from the test demo program that is available for download on crystalfontz website.
the problem is i am not able to receive responses from the lcd.
the test program times out waiting for response. when i modified the delay in test program test633.c from 10000 to 1000000 i got response for only one line that was written. so i further modified the program to send command and wait for response in a loop.
and the lcd sends back a response every alternate time. when i tried the same thing for other commands. commands seem to do their work. but the lcd fails to generate response. anybody come across a similar problem and figured out a solution?

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New member
i figured out the problem. apparently getty was running on my serial port :rolleyes: . that seems to have been causing all this problem. my lcd seems to be working fine. :D.
USB LCD Displays - Graphic and Character LCDs with a Keypad

CF Tech

Thanks for letting us know what was going on. I'm glad that you were able to get it working.