[sdiy] Cheapo LCD display

[Scott Gravenhorst]

Eric Brombaugh <ebrombaugh1 at cox.net> wrote:
>On 09/25/2009 02:17 PM, Scott Gravenhorst wrote:
>
>> Nice work, Eric.  I like Earl - what/where is he from?
>
>Thanks!
>
>Earl is the main character in a comic strip called Red Meat:
>
>http://www.redmeat.com/redmeat/
>
>They used to carry that in our local alt newspaper. No longer, but the 
>website is still active. Red Meat is rather... odd.
>
>> I need to get to work on an LCD project of my own, I bought a graphics LCD 128x256 at
>> All Electronics for a few bucks -$12?, I have all of the docs and they look like they
>> match the unit.  Wiring it will be a little weird, I need to just dive in and do it.
>> I think I saw a 640x480 unit for less than $20 in the All Electronics catalog last
>> week.  Dunno if it's color, my unit is not.
>
>I've found that the physical interface to these LCDs is usually the 
>biggest stumbling block. Electrically they're not so bad - usually 
>either SPI or some simple parallel interface. Shouldn't be too tough to 
>get yours going.

That seems all described in the docs, so I'm confident there.  What do you mean by 
"the physical interface to these LCSs..." ?  I think you started with much more "raw"
material than I have - the board I have has several interface ICs on it, I will 
interface only with the electrical connections to the ICs.

>> My strange way of doing this will be to get it working using an FPGA directly
>> interfacing with the LCD.  I can use PicoBlaze as a microcontroller.  Once I get it
>> working there, I should be able to fairly easily port it to the PIC board I bought for
>> it.  (I have fewer problems troubleshooting a Verilog design than I do a PIC design)...
>
>Nothing wrong with that. Only downside is that it's a bit more fiddly 
>work coding for the Picoblaze in assembly than doing it on a standard 
>MCU with a C compiler. Otherwise it's all just bits.

Heh, that's kinda funny because I'm quite comfortable in the stunted runt environment of PicoBlaze.
 Hell, if I can make something work there, it should be child's play even with the weirdness of a
PIC [grin] and a rather large/nice one at that (PIC18F8720).  The reason I like this method is that
the reprogram cycles with an FPGA are infinite where they are limited with a PIC.  (I know, I'm
being anal).  I can fix the doofus things in the FPGA design phase...  I need the practice anyway...

>Let me know how it goes.

You all will be the second to know when I get it going.

-- ScottG
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-- Scott Gravenhorst
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