13 Jan
2013
13 Jan
'13
2:33 p.m.
On 1/13/2013 1:11 PM, Dave McGuire wrote:
Cool. And I misspoke -- the QRGB-GRAPH does support DMA, so it might be
fast enough for DOOM after all :).
- Josh
On 01/13/2013 04:03 PM, Josh Dersch wrote:
Yeah. I need to do some un-modification to the boards before they'll
work properly. They were modified for use at the University of
Rochester for capturing images of some sort of laser application (the
QRGB-GRAPH does frame grabbing as well as display) and seeing as how I'm
unlikely to own such a laser at any point in the future, it's not of
much use as is :). Fortunately I have the specs for the modifications
so it should be easy to undo (or redo if I do come across a high-powered
laser I need to take photos of.).
I have a set of Matrox QRGB-GRAPH (and QVAF-512)
boards (Q-Bus color
graphics for the PDP-11) which I have yet to play with. I don't think
it'd be a good candidate for anything that requires rapid full-screen
updates, though -- in particular there's no facility for blitting a
graphics region from the -11 to the graphics memory (everything is
drawn on a pixel-by-pixel basis through a set of registers).
That sounds like serious fun anyway! Were
there any PDP-11 graphics systems that actually had a memory-mapped
framebuffer?
Yes, the AED 512 and 767 have a Qbus interface that (I believe) uses
DMA, in addition to the standard RS232 port.
-Dave