Page 1 of 1

PR9-B PASSWORD DOOR SECURITY LCD

PostPosted: Tue Dec 22, 2015 12:51 pm
by afz2004
Hi all. I'm having slight problem here. I made this project on strip board first of all and the problem is that, the LCD giving out all black square display. I have checked many many times if there are any unconnected pins, shorted and so on. Still no idea what is the problem. Even I plug my LCD on SK40C LCD port, it gave the same problem. May I know what is the resolution for this problem? In mean time, I just used default HEX file provided by Cytron. Thanks in advance.

Re: PR9-B PASSWORD DOOR SECURITY LCD

PostPosted: Tue Dec 22, 2015 12:52 pm
by afz2004
I even changed many ICs already, and checked if there is any error or damaged. It still in good condition

Re: PR9-B PASSWORD DOOR SECURITY LCD

PostPosted: Tue Dec 22, 2015 2:10 pm
by ZaM
check your crystal frequency because if you using cytron hex file its should be 20Mhz.

Re: PR9-B PASSWORD DOOR SECURITY LCD

PostPosted: Tue Dec 22, 2015 3:18 pm
by afz2004
ZaM WROTE:check your crystal frequency because if you using cytron hex file its should be 20Mhz.


ok. but when I ran this circuit in Proteus, I didn't see any changes even I used 24Mhz. So if the crystal is not the problem, what else can you suggest?

Re: PR9-B PASSWORD DOOR SECURITY LCD

PostPosted: Tue Dec 22, 2015 3:51 pm
by ZaM
proteus is not realible to run pic code, even LED blinking code cannot run because of timing. if not wiring error, then it crystal, and you cannot use PR8 code on SK40C to test LCD because RS and EN pin use other pin/port. maybe you can use SK40C+LCD with SK40C code, if not found code for pic16f877a, try find in tutorial. One more thing, how do you upload the code to PIC? can you measure the voltage at:
pin 1(release reset button):
pin 1(press reset button):
pin 11:
pin 12:
LCD pin 3 minimum voltage:
LCD pin 3 maximum voltage:
Connectivity LCD pin DB0 with RD0:

Re: PR9-B PASSWORD DOOR SECURITY LCD

PostPosted: Tue Dec 22, 2015 3:58 pm
by ZaM