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SED1335 LCD with 68HC11 Problems

Started by heyheyitsdavid April 28, 2005
I am attempting to connect an Epson SED1335 Graphic LCD Display to a
68HC11 mounted on either a FOX11 or EVBplus2 board (have tried both).
I have Stepped through the SED1335's datasheet completely, creating
assembly code for each instruction and have not had any luck getting
the LCD to display anything. It would be very helpful if I could
possibly get some working code to look at to see what I am doing
wrong. If anyone has an assembly program for the SED1335 that they
would be willing to share with me it would be greatly appreciated.
(The code does not necessarily have to even be for the 68HC11, as I
could port the code over from another assembly language if need.)

Thanks,

David Bowker
ddbowker@ddbo...




In a message dated 4/28/05 8:39:27 P.M. Eastern Daylight Time,
ddbowker@ddbo... writes:

I am attempting to connect an Epson SED1335 Graphic LCD Display to a
68HC11 ===================
Are you trying to memory map it on the memory bus using R/W and E, or are
you 'bitbanging' it on io ports? (sometimes bitbanging is slow but sure... you
can control the delays since every byte is programmed io)


--- In 68HC12@68HC..., BobGardner@a... wrote:
>
> In a message dated 4/28/05 8:39:27 P.M. Eastern Daylight Time,
> ddbowker@c... writes:
>
> I am attempting to connect an Epson SED1335 Graphic LCD Display to a
> 68HC11 > ===================
> Are you trying to memory map it on the memory bus using R/W and E,
or are
> you 'bitbanging' it on io ports? (sometimes bitbanging is slow but
sure... you
> can control the delays since every byte is programmed io) >

I am trying to write to the display memory using R/W and E. How could
I 'bitbang' the ports to get it to display?




In a message dated 4/28/05 10:10:44 P.M. Eastern Daylight Time,
ddbowker@ddbo... writes:

I am trying to write to the display memory using R/W and E. How could
I 'bitbang' the ports to get it to display?
==============================
You need a whole port for data, and a couple lines for chip select, r/w, e
and cmd/data or register select or a0 or whatever its called (all 3 are
equivalent). To write a byte, put the data, assert cs, w, a0 and raise and lower e.
Repeat as necessary.


If you can port from 51 asm look here:
http://www.hantronix.com/down/3224app.pdf This is for HC08 or HC05. Don't know if it's working but initialization
sequence looks good:
http://www.telesys.ru/wwwboards/mcontrol/520/messages/258563.shtml Did you check LCD panel voltages, adjust contast ?

Are you sure SED1335 in your LCD module is configured for 68xx bus (E and
R/W signals)? LCD module I've got doesn't have jumper to select between
E+R/W and /RD+/WR, SEL1 pin isn't wired to connector and datasheet doesn't
mention if SEL1 pin is pulled down or up.

SED1335 A0 pin is bit confusing. You write data to A0=0 but read it from
A0=1.

Edward ----- Original Message -----
From: "heyheyitsdavid" <ddbowker@ddbo...>
To: <68HC12@68HC...>
Sent: Friday, April 29, 2005 3:37 AM
Subject: [68HC12] SED1335 LCD with 68HC11 Problems >I am attempting to connect an Epson SED1335 Graphic LCD Display to a
> 68HC11 mounted on either a FOX11 or EVBplus2 board (have tried both).
> I have Stepped through the SED1335's datasheet completely, creating
> assembly code for each instruction and have not had any luck getting
> the LCD to display anything. It would be very helpful if I could
> possibly get some working code to look at to see what I am doing
> wrong. If anyone has an assembly program for the SED1335 that they
> would be willing to share with me it would be greatly appreciated.
> (The code does not necessarily have to even be for the 68HC11, as I
> could port the code over from another assembly language if need.)
>
> Thanks,
>
> David Bowker
> ddbowker@ddbo... >
> Yahoo! Groups Links >



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