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Not enough memory for a frame buffer?
Posted: Fri Jun 11, 2010 11:41 am
by Folknology
For those folks that complain about lack of memory on the L1/G4 chips you should take a look at what this guy has done:
http://rossum.posterous.com/20131601
I love the way he has tackled the problem and the results are fantastic, just imagine what this guy could do with an Xmos chip!
regards
Al
Re: Not enough memory for a frame buffer?
Posted: Fri Jun 11, 2010 12:25 pm
by jason
Nice! Does anyone know who this guy is?
EDIT: I found him elsewhere.
Re: Not enough memory for a frame buffer?
Posted: Fri Jun 11, 2010 12:39 pm
by leon_heller
I've got one of those LPCXpresso kits.
Re: Not enough memory for a frame buffer?
Posted: Fri Jun 11, 2010 3:37 pm
by Berni
Now thats some impressive stuff i saw an AVR do a similar thing but with VGA. This is a old trick to generate the images line per line insted of frame per frame, i can imagine this makes programming a lot harder since you have to always render the next line of video needed to display.
I bet he would love to have a xmos chip for this so that those time critical tasks can run truly simultaneously.
Oh yeah and i have one of those at home too!
Re: Not enough memory for a frame buffer?
Posted: Fri Jun 11, 2010 4:27 pm
by lilltroll
Ahaa, I have been programming the XDK screen the hole night, and with so many MIPS it's amazing what you can do without any buffer on the fly. But I will try to adopt the line buffer!
I looked at some old 3D examples from the XLinker forum, and realized that many things could be done in much more instruction efficiently ways. I am a C rookie, but I'm not afraid of mathematics as conformal mappings. Anyway, there is probably so many smart tricks to learn in general.
I once had the Amiga 500, and it could run a simple 3D-flight simulator!
PS. I like the R-2R converter solution, wouldn't it be very easy to use on XMOS? .DS
Re: Not enough memory for a frame buffer?
Posted: Fri Jun 11, 2010 5:40 pm
by Andy
Someone on xlinkers did pretty good VGA graphics using R2R DAC. Not sure if he's on XCore.
Re: Not enough memory for a frame buffer?
Posted: Sat Jun 12, 2010 11:03 pm
by otitov
line buffer approach - very nice!
so On Screen Display (OSD) could be made with this method, right?
Re: Not enough memory for a frame buffer?
Posted: Sun Jun 13, 2010 10:13 am
by Berni
Actually someone made a OSD with a PIC12F. With OSD you can use a nice cheat. What he did was simply pass the input signal directly to the output but wire a I/O pin on to it. The pic would then look for a sync pulse and then waits for the pixel he wants to change, at that time the I/O pin is switched out of tristate mode in to logic 1 ( for white) or logic 0 ( for black)
Then also saw someone use a AVR to additionally sample a few pixels using the ADC and use them to track motion, later displaying a OSD with a motion controlled game.
Someone should give these concepts a try with the processing power of a xmos chip.