Errrrrrrr.....a lil help

**oliffied** · 05-25-2005, 08:39 PM

Hey,
I was wiring up my LCD character display last night, and in the guide i was using it says for the register select LCD pin i need to use the wire coming from the parallel printer port pin 16....there aint no wire on pin 16.....so i was wondering if anyone knew wtf i should do.....
catch

btw..lcd from www.jaycar.com.au
found printer cable lying around...

**volvo9** · 05-25-2005, 09:01 PM

Have a little more info? What schematic are you using to wire up the display?

Is the display HD44780 compatible?

I wired up one before, but I didn't run into such troubles, the parallel port has 25 pins, so why are you saying you don't have a pin 16? does the cable not have it?

**jcdillin** · 05-25-2005, 09:21 PM

ditch the printer cable, get a actual DB25 connector. the register select pin is going to be needed.

**oliffied** · 05-26-2005, 12:18 AM

Yeah the cable has no pin16...im like wtf...could any other wire on a different pin do the same thing?

will trial and error work? or will that screw the display??

i was using this guide http://www.overclockers.com.au/techstuff/a_diy_lcd/
and yeah as far as i know its HD44780 compatible.

thanks

**nzKAOSnz** · 05-26-2005, 08:47 PM

oh - be careful - some of those lcds - the contrast is between -5v and 0, NOT 0 and +5v. I have killed one doing that.

**jcdillin** · 05-26-2005, 08:58 PM

Originally Posted by oliffied

Yeah the cable has no pin16...im like wtf...could any other wire on a different pin do the same thing?

will trial and error work? or will that screw the display??

i was using this guide http://www.overclockers.com.au/techstuff/a_diy_lcd/
and yeah as far as i know its HD44780 compatible.

thanks

yeah, to keep things safe, I would really just take the time to find the proper connector, i've wasted countless hours fussing around with printer cables for LCD's when in the end I usually end up getting the right connector or blowing out my LCD.

**Jahntassa** · 05-26-2005, 09:01 PM

RatShack used to have straight DB25 connectors that had all the pins. Sometimes they'll make cables without all the pins as cost-savings.

**nzKAOSnz** · 05-26-2005, 09:28 PM

or jst make your own. Go and get a 16 or 25 pin data cable and the male DB25 connector. and enjoy soldering 25 pins

If you use a 25pin cable- get the 14odd data pins all wired - then split the remaining wires into +5v and gnd. I figured that between them - they should be able to carry the current to run the lcd. i think i had 5or so for each rail. that means theres only one cable to run - and the molex connecter just comes from the DB25 connecter on the computer end

i did that coz i needed a really long printercable. (Under seat -> dash)

**nzKAOSnz** · 05-26-2005, 09:30 PM

also - make sure you use a detachable connecter at the LCD end. YOU WILL REGRET IT IF YOU DONT!
i did - and half my tracks lifted. so i have some dodgy soldering - but it works.