Converting LCDs to VFDs

chiark · Post by **chiark** » Wed Feb 06, 2002 7:59 am

A rather strange request this one. I am using a LK202-25 for my <a href=http://www.chiark.com/scooby/limp.asp>in-car MP3 player</A> but, as you'd expect, I've found that I really should have ordered a VFD.

Soooo, after a bit of research, I've found that Noritake make a direct LCD replacement VFD that has the same pin-outs and commands (HD44780) as the LCD part used by the LK202 (Ampire)

Question is, can I remove the LCD and simply strap on the Noritake VFD, thus making my LK202-25 into a VK202-25? The only difference is that the LCD uses a varirable voltage on pin 3 to control contrast whereas VFD requires a command sending to change brightness. (Am I best off leaving Pin 3 disconnected?)

The VK manual lists a Brightness command, and the LK manual doesn't, but I'm guessing that they both use the same processor boards given that the board says both LK and VK on it... Some other commands are different, but nothing radical apart from Startup screen. There's no "overlaps" in the command set.

Anyone have any ideas? Thanks in advance

chiark · Post by **chiark** » Wed Feb 06, 2002 8:05 am

PS - I realise that this may void any warranty

chiark · Post by **chiark** » Thu Feb 07, 2002 11:58 am

It works

Post by **Henry** » Thu Feb 07, 2002 12:02 pm

the $20 dollaer question is, what happends when you try and send the contrast command to the LCD/VFD...

chiark · Post by **chiark** » Sat Feb 09, 2002 8:34 am

The answer is...

"Nothing"

Where do I claim my $20?

BTW, I wouldn't recommend this as an easy hack unless you're more proficient than me at desoldering!!!

relix · Post by **relix** » Sat Feb 09, 2002 12:45 pm

at first I thought you would just replace the whole module, but now I see that you actually took of the LCD off the PCB
nice that you've succeeded!

chiark · Post by **chiark** » Mon Feb 11, 2002 2:02 am

Exactly - I found a local supplier of the Noritake units that was cheap...

The web is such a useful resource. In two hours, I found that the Noritake module was compatable with the Ampire unit.

I had to hack two pins off the connector (15+16) which power the backlight, but that is literally it.

"Plug and play".

(Well, attempt to desolder, curse, try again, try harder, curse more, clean pins, fit new unit, re-solder, resolder again, curse more, clean off solder, start again, curse, bask in reflected glory of VFD light

)

relix · Post by **relix** » Tue Feb 12, 2002 3:07 am