Microcontroller for serial->LCD interface

[Tha PiRAyA]

I have an old LCD screen from an Olivetti M10 (the same screen as the
Tandy M100), which I wish to interface with my PC. It is a 240x64 b/w
graphical display, controller by 10 HD44102 ICs. The control signals
to the LCD are esentially an unmultiplexed row/column selector for the
44102's, and an 8-bit bus which communicates with the currently
selected IC.
What I need is a microcontroller that can be programmed to interface
the RS232-port on my computer (or, failing that, the LPT port) to the
LCD.
In it's simplest form, it should accept serial input, and have enough
outputs to be able to select the HD44102 (10 bits, or just 4 bits fed
to a demultiplexer), and 8 bits data for the IC.
The interface doesn't *have* to be bidirectional, since most of the
work will be done by the PC and it wouldn't take too much to make the
program 'know' what's on the display without reading back display
memory. But it would be nice if it was possible.
I'm looking for a relatively cheap uC, one with flash or EEPROM for
fast reprogramming, and which is not too hard to program. I have only
programmed a couple of uCs before, they used ASM which I think will
get the job done here.
I am thankful for any suggestions, tips, ideas etc. thay any of you
might have regarding this project.

 

[Tha PiRAyA]

- Remember that I did not say that a PIC is the only way...

Yes, but it seems like a good way.

- Forget the F84, a 16C is not flash, so 16F87x is the only choice,
and not a bad one, but I would pick a 16F877
- BTW I sell PICs over the 'net, but you might not like buying from
far away

I saw that after posting, maybe I'll end up buying from you (I live in
Sweden).
The 16F877 doesn't have an UART, and ELFA doesn't carry this chip
either.
What is a MSSP, and can it be used to run RS232-communication? I'm new
to PIC terminology and a web search didn't explain everything...

A programmer, power supply, target circuit, and of course a PC with
software.

The only programmer I could find on ELFA seems to be the ISP-PRO
(http://www.basicmicro.com/Products_PICMicros.aspx?CategoryID=33) with
adapter card.
This one supports most 16x PICs and a few others.
I've got a 12V power supply from an old laptop, or I may take the
power from my computer.
I would prefer to use free/open source software, the platform I'll be
running on is either DOS or windows XP.

I would prefer a 16F877 (much more memory etc), or if you can get it
an 18F, for instance an 18F452. Note that a 16F877A is cheaper than an
16F877, but check whether you programmer supports it.



Wouter van Ooijen

-- ------------------------------------
http://www.voti.nl
PICmicro chips, programmers, consulting

Thanks for the advice.
I'll not be able to actually begin the project in a few weeks time,
but it helps having a good idea about how to do it.

 

[Tha PiRAyA]

It does, but it is called USART

OK, I only looked on your table of PICs when i tried to select one.

No, it is for SPI and I2C


- if you have plenty of time: try one of the 'trivial' or 'zero-parts'
programmers

- 16F87x'a can be programmed with LVP
- check my Wisp628
- maybe consider using a bootloader (my WLoader, that page has links
to other bootloaders)

It would be best if I could build a simple programmer myself. The
programmer this guy is using looks very simple, would it be possible
to build something similiar for the 16F87x?
Link: http://www.piclist.com/techref/piclist/biketut/chapter4.html#zzee_link_2_1019487432

- wisp628 fimware & software is available for DIY, but not fully free
- check ponypog and/or icporg: free but not open source
- some programs don't work on DOS, some don't work on protected
Windoze (like XP)

I got ICPROG (with a win2k driver, should probably work in XP) and
MPLab IDE 6.3 from Microchip. Would I need more/other software than
that? I am reading up on PICs at
http://www.mikroelektronika.co.yu/english/product/books/PICbook/picbook.htm

 

[simon]

Look at http://pp06.sourceforge.net for open source
dos/win9x/winNTetc/linux software that does most 12 and 14 bit pics on
a variety of parrallel port programmers.

You will likely also find Realterm is useful for debugging the serial
comms, or even to run the display.

http://realterm.sourceforge.net

 

[Uncle Wobbly]

there is a really nice USB ( powered) PIC programmer from these people... I
got one and I'm very pleased with it.

http://www.fored.co.uk/Eindex.htm

 

[Uncle Wobbly]

agreed it is top end, but it is very versatile and with nothing else to do
but plug it in....