Nigel,

I've had a hard time getting my 320x200 graphics display with the Seiko
SED1335 chipset to work.  I'm using an F84 with an i2c port expander
(Philips PCF8574) for the 8-bit data bus (at least the i2c stuff is working
even if the display isn't :) ) and 3 I/O pins for read, write and address.

The Seiko documentation wasn't very helpful for me. They even had a
pseudo-code example but it didn't help either (my brain must be fried).  Do
you have any code (even just a snippet showing initialization) that you can
share?

Thanks in advance,
Jeff

-----Original Message-----
From: Nigel Orr [mailto:nigel@AXONINSTRUMENTS.CO.UK]
Sent: Tuesday, November 26, 2002 4:18 AM
To: PICLIST@MITVMA.MIT.EDU
Subject: Re: [PIC]: Large LCD...


> I'm experimenting with using a large LCD - 320x200 pixels.
>
> It is setup as a graphic display.
>
> It is mono, and has 4 bit input (so, to input a full screen
> worth is 16,000
> pulses)

Have a look at LCD controller ICs, I've used the Seiko SED1335 before,
there's a similar toshiba one (3693c or something like that...).  You add
the controller and a suitable ram (basically video RAM), and it does all
the pulse timing stuff for you.

You only need to talk to the controller when you want to change the
display, not continuously, which is probably a better plan than using a
dedicated PIC to control it.  They also do things like page switching, so
you can build a screen in the background and then switch to it instantly.

The 1335 also includes a built-in font, though you can use your own if you
prefer, or add some custom characters to the built in one.

It needs an 8-bit data bus, read, write and one address line (used to tell
it whether you are sending commands or graphics/text characters).

HTH,

Nigel

--
Nigel Orr, Design Engineer                     nigel@axoninstruments.co.uk
Axon Instruments Ltd., Wardes Road, Inverurie, Aberdeenshire, UK, AB51 3TT
              Phone: +44 1467 622 332   Fax: +44 1467 625 235
                      http://www.axoninstruments.co.uk

--
http://www.piclist.com#nomail Going offline? Don't AutoReply us!
email listserv@mitvma.mit.edu with SET PICList DIGEST in the body

--
http://www.piclist.com hint: To leave the PICList
mailto:piclist-unsubscribe-request@mitvma.mit.edu