Sigma Designs' video card for SE/30 — #15

Post #15 by zuiko21

Source Forum	68kMLA
Category	Hardware
Post Date	Thu, 10 Nov 2011 - 19:25
Original URL	https://68kmla.org/bb/threads/sigma-designs-video-card-for-se-30.24189/

Post

The PowerPortrait is listed in that ad as "for the SE/30" because it's a SCSI interface.

LOL. My bad! Didn't notice the SCSI part... :I

Well, a multimeter to work out which pins short to (ie, are) ground is probably a good start.

Good advice. Most of the "danger" of mistaken connections between the several DE-9 PC video ports should be related to applying a higher-than-expected frequency sync to a fixed resolution CRT, though.

Scoping the other pins for signals would depend on convincing the card to output an image though, I guess.

I'm afraid so... Apple's cards won't supply any output signal if no monitor is connected -- so I should know which are the sense pins, if any.

Do integer divisions of any of those frequencies produce any familiar numbers?

Doesn't seem so... again, 62.955 divided by four makes 15.73875 MHz, which is very close to the 15.6672 MHz of the Xtal on 68000 Macs -- incidentally, the dot clock of B&W compacts.

More experiments with my card: since the second SE/30 where the card came in is currently taken apart for cleaning, I attached it to my first SCSI-less SE/30, copying the PageView control panel on a diskette with System 6.0.7 -- couldn't find a (reliable) System 7 disk with enough space! While booting, an error message appears:

Code:

The PageView software can only be activated if the Sigma Designs PageView monitor has been properly installed.

Please use the Monitors Control Panel to check your configuration.

After clicking OK, the icon appears crossed. After that, everything seems normal -- the Monitors CP shows nothing out of the ordinary... I should really learn about the connector's sense pins