Re: LCD module - PC Parallel port

Neo wrote:
I am using HD44780 based 2x16 character LCD Module. (Model : CCS1620CSL) I am using it in 8-bit, 2line mode.





I've wired up the LCD module to the Parallel Port of PC as shown here : http://www.codeproject.com/csharp/cspplcds.asp



Nothing appearing on LCD except 16 black boxes. No effect of init routine.



Signals on Parallel port is working fine. I've checked them using multimeter.Still there is no activity on the display except 16 black box.



One thing is - signals on parallel port are as follows:

2.48 V for Logic 0

5.5 V for Logic 1



Can this be a problem? Any ideas???



Thanks and Regards,

-Neo




I don't know if the parallel port wired correctly, but the resistor
on pin 3 of the LCD should be a 10k pot, wired between +5 and GND
and the center of the pot to pin 3 of the LCD. Right now you have a fixed contrast and you want it variable.
rw
.

Relevant Pages

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