zben@umd5.umd.edu (Ben Cranston) (11/29/89)
Tried to install the "video hack" on my II CX last night, and I *think* I
followed the instructions, but the icon comes up crossed-out and the buttons
that are supposed to be visible in the CDEF window aren't there, with the
exception of the "filter" button which is grayed out.
Did this with the standard monitor plugged in, hoping to see the screen start
rolling when the synch rate changed. Do I need to unplug the Apple monitor?
Found a circuit for a color combiner but it needs a "chroma key" input.
Is this just a back-porch-time flag? Is it available or derivable from the
video card's DB9 anywhere, or do I need to build a circuit to follow the
composite synch and regenerate it?
Dox for vhack say composite video comes out the "green" pin. Is it reasonable
to expect to be able to build a color combiner to get RS170 color signal?
Are boxes to do this available commercially?
--
Sig DS.L ('ZBen') ; Ben Cranston <zben@Trantor.UMD.EDU>
* Network Infrastructures Group, Computer Science Center
* University of Maryland at College Park
* of UlmPalevich@apple.com (Jack Palevich) (11/30/89)
In article <5691@umd5.umd.edu> zben@umd5.umd.edu (Ben Cranston) writes: > Tried to install the "video hack" on my II CX last night, and I *think* I > followed the instructions, but the icon comes up crossed-out and the buttons > that are supposed to be visible in the CDEF window aren't there, with the > exception of the "filter" button which is grayed out. I was wondering when people would ask about this. I think you have a "new" Apple Macintosh II Video Card, as opposed to a "classic" Mac II Video Card. You can tell which card you have by going to the Monitors CDEV and pressing the Option key. If the little dialog box says: Macintosh II Video Card <-- you have the classic card. Mac II High-Resolution Video Card <-- you have the new card. At the time I wrote the Macintosh II Video Card Utility, the new card was not announced, so I couldn't mention it in my documentation. The new video card is pretty much identical to the classic video card, but it does have one additional feature: It senses the kind of monitor you are using and adjusts its video output to match the monitor. This means that it automaticly switches to RS170 rates when it senses that a RS170 monitor is connected. > Did this with the standard monitor plugged in, hoping to see the screen start > rolling when the synch rate changed. Do I need to unplug the Apple monitor? Yes, you do need to unplug the Apple monitor, and plug in you new cable, to have the new video card use the RS170 rate. Once you do that, you will get a 4-bit per pixel, 512 x 384 screen. This screen size was chosen to look good on Apple's RS170 rate RGB monitor. (This monitor is normally used with the Apple IIgs, but you can plug it into the "new" Apple Macintosh video card, too.) Without my Video Card Utility, this 4-bit-per-pixel mode is the only mode you get. If you install my utility, then you can also choose a 1-bit-per-pixel flicker-free mode. > Found a circuit for a color combiner but...(a hardware question follows) I don't know -- I'm just a software guy. I did this utility so that I could video tape some HyperCard stacks. > Dox for vhack say composite video comes out the "green" pin. Is it reasonable > to expect to be able to build a color combiner to get RS170 color signal? Yes. Unfortunately the "flicker filter" option only works in black & white. > Are boxes (available) to do this available commercially? Yes. I can't suggest any specific brands, but I have used several, and they all cost around $400, and they all worked pretty well. Jack Palevich, Meerkat Handler Apple Computer, Inc.