propeller VGA display terminal program
David B
Posts: 592
I've got a homemade desktop propeller prototyping platform, and think I may have destroyed its 2-line serial LCD display last night by stupidly running a motor from the shared power supply.
I've always only used little 2-line LCDs for a propeller display; I've never gotten into TV or VGA displays. But I've got a spare 16" LCD VGA display that somebody gave me, and started looking into using the propeller VGA driver to replace the serial LCD.
It would be great to get the display capability of a full screen, but it looks like VGA takes a full 8 IO pins and a large chunk of memory, which is a big bite out of a general purpose prototyping board as compared to the one pin of the serial LCD.
Has anyone created a standalone display unit by dedicating a propeller to driving a VGA display, and accepting serial input from a remote source? Sort of like a display terminal from the old days? That seems like it would be a really handy utility, but I didn't see anything like that on the OBEX.
I've always only used little 2-line LCDs for a propeller display; I've never gotten into TV or VGA displays. But I've got a spare 16" LCD VGA display that somebody gave me, and started looking into using the propeller VGA driver to replace the serial LCD.
It would be great to get the display capability of a full screen, but it looks like VGA takes a full 8 IO pins and a large chunk of memory, which is a big bite out of a general purpose prototyping board as compared to the one pin of the serial LCD.
Has anyone created a standalone display unit by dedicating a propeller to driving a VGA display, and accepting serial input from a remote source? Sort of like a display terminal from the old days? That seems like it would be a really handy utility, but I didn't see anything like that on the OBEX.
Comments
http://www.brielcomputers.com/files/PTfirmware.zip
It was used in PocketTerm, a Propeller terminal which pretty much does what you are doing. Should adapt pretty easily to your project.
OBC
as the "main" computer. I have to admit, I've thought about that as well.
The trick would be passing text or graphics to the display controller. If done via serial (saves a bunch of pins) the
you'd quickly run up against response time, and if done parallel, t would take more pins - say 8 for data and ANOTHER
ONE as a strobe? That's nine pins now. Not exactly helpful from a pin count stand point, is it?
Graphics might be nice, but my main use of this would be for general purpose text and number display while working on any random prop project.
Speed would be nice, but as often as not, the project I'm working on is itself so slow that I don't see response time as an issue for my needs.
So far I've got nothing for a "display".
The easy step would be to use the PST (Prop Serial Terminal) program,
But I've not even started with that yet.
Eventually, it WILL become an issue.
An it WILL need a solution.
TV can also be used, and it can be done with one or two pins. If it's just text, a monochrome signal renders up to 64 columns on the average TV display and most LCD displays. Some displays may do 80, depending.
Personally, I like to run a TV driver into a capture card that displays the image on my PC in a window. TV works great for that, particularly monochrome displays.
You could drop down to 3 pins easily, as your LCD is monochrome.
Memory could also drop, if you limit the chars, which is also what your LCD has now...
So, a good target would be a "COG-Only" 3 pin 'place in the corner' Status display ?
Point.
Maybe even set and match.
I gotta see how much that costs.