Apple Two Page Display - NuBus Card Required?

[warmech]

I've come into possession of an Apple TPD that works (but needs some attention), but I can't get a signal out of any of the Macs I've hooked up to it. Does this thing require a TPD NuBus card to drive regardless of the Mac? My Apple portrait display hooks right up to a IIsi with no issues, for instance; does the TPD just flat out have to be driven by it's corresponding card? If so, does it have to be an Apple TPD card, or will a Radius TPD card work?

 

[Trash80toHP_Mini]

Portrait is the best you'll get out of anything with onboard video in the Macintosh II/68030 series. I'm of the opinion that it's the only really usable resolution they output, but I'm a pixel hog. 8bit Color on a smaller screen can be useful, maybe for gaming? So you will need a NuBus card for anything Macintosh II/whatever.

The first Mac to drive Apple's TPD out of the box was the Quadra 700. Pretty sure all the Quadras and the LC475 can drive it, at least until they reined the Quadra 630 in at 16" video without Portrait support. GRRRRRRRR!!!!!!!!!!!!!!!!!

 

[warmech]

Hmm... my Q800 did bupkis; I may try with the Q950. Outside of that, though, would a Radius TPD card work, or is Apple the only way to go?

Also, laaaaaame on the 630 (which also explains why my 650 didn't do anything, lol).

Edit: Well, the 950 also does nothing. There's a flicker on the raster as it boots, but nothing beyond that. Bad monitor? It almost certainly needs a recapping anyway.

Second Edit: I guess I should clarify - the TPD uses the same cable as the Apple mono portrait display, right? That's what I've got it hooked up with at the moment, so I hope that's not the wrong cable, lol.

 

[Trash80toHP_Mini]

Wrong cable for sure, not the same! Cheaper than a NuBus card that'll drive that grayscale beast!

 

[Melkhior]

They need a different sense code: https://github.com/sfiera/mactech/blob/master/displays.rst, so the cable from another screen is is unlikely to work.

As the monitor seems to use a 13W3 connector, the cable might be difficult to replace. An easy solution would be to make a male/female DB15 adapter and wire everything but the sense codes pass-through; for the sense code, 4 & 7 would be floating and 10 would be grounded to signal the 21" B&W. Or you can look up the pin-outs of the 13W3; if it's the same as Sun or SGI (they're different!) you might be still be able to find a VGA <-> 13W3 cable meant to plug a Sun monitor on a PC and connect it to the adequate MAC <-> VGA adapter.

 

[Trash80toHP_Mini]

He already has a 13W3 to DA15 cable the reverse of what I had, it just doesn't work as it has coding for Portrait built in. I had the reverse problem, the cable I bought was supposed to work with both displays, but yielded only TPD scrunch on the Portrait. The engineer at the mfr walked me through what I needed to do with the lines in building an adapter. Used a DB25 jumper wire passthru dongle cut down to DA15 on the connectors. Bodge worked a treat.

 

[warmech]

Stupid sense codes, lol. I have an old rat's nest of a cable for my portrait that I can repurpose with the right sense lines wired up; I'll report back with an update shortly!

 

[warmech]

Eyyyy - it lives! Desoldered sense line seven from my old handmade portrait display cable and voila! The geometry is... off, but the image is there. The previous owner recapped the PSU, so the two other boards will need the same.

There is one minor issue, however, that someone here may be able to address. The brightness potentiometer on the video PCB (not the one on the side of the case) has had its wiper dial broken off at some point in the past, so I have no idea what its value is (as the dial is where it is stamped). Would y'all happen to know what value that it or be able to check your TPD for reference? I hate that there are zero schematics out there for these things (or the portrait displays). Alternatively, can you determine the value of a pot with a multimeter with no wiper present?

Thanks, y'all for the help! This was the easiest fix I've done in a good long while.

 

[warmech]

They need a different sense code: https://github.com/sfiera/mactech/blob/master/displays.rst, so the cable from another screen is is unlikely to work.

As the monitor seems to use a 13W3 connector, the cable might be difficult to replace. An easy solution would be to make a male/female DB15 adapter and wire everything but the sense codes pass-through; for the sense code, 4 & 7 would be floating and 10 would be grounded to signal the 21" B&W. Or you can look up the pin-outs of the 13W3; if it's the same as Sun or SGI (they're different!) you might be still be able to find a VGA <-> 13W3 cable meant to plug a Sun monitor on a PC and connect it to the adequate MAC <-> VGA adapter.

Also, thank you so much for pointing this resource out! I had no idea this existed and it's incredibly useful!

 

[Trash80toHP_Mini]

That looks like Portrait Stretch but the angle's strange. Do a screen shot and take a look at the file to see if that's still portrait resolution.

 

[warmech]

That looks like Portrait Stretch but the angle's strange. Do a screen shot and take a look at the file to see if that's still portrait resolution.

Ah, yeah, that's probably my fault. I was trying to determine if it was having a linearity issue last night and dialed the geometry waaaaaay down. It should adjust back up to scale just fine (and a recap won't hurt either).

 

[Trash80toHP_Mini]

Don't think that's the problem, do a screen shot so you'll know if it's Portrait or TPD resolution in the video buffer. Looks to me like you cable is telling the Mac to output Portrait. In that case the TPD stretches 640 pixels across its 1152 pixels worth of phosphor. Hence, Portrait Stretch would be the opposite of TPD Scrunch, when a VidCard (or Mac) is told by the incorrect cable to output TPD and the Portrait dutifully condenses 1152 pixels across its 640 pixels worth of phosphor.

Command, shift,3 is your friend!

 

[warmech]

Don't think that's the problem, do a screen shot so you'll know if it's Portrait or TPD resolution in the video buffer. Looks to me like you cable is telling the Mac to output Portrait. In that case the TPD stretches 640 pixels across its 1152 pixels worth of phosphor. Hence, Portrait Stretch would be the opposite of TPD Scrunch, when a VidCard (or Mac) is told by the incorrect cable to output TPD and the Portrait dutifully condenses 1152 pixels across its 640 pixels worth of phosphor.

Command, shift,3 is your friend!

The heck - C+S+3 worked all the way back then? I'll grab a screenshot in a moment and let you know.

 

[warmech]

Grabbed a screenshot and snapped a photo for reference after trying to reset the geometry a bit. The linearity is off a bit at the bottom, but it's otherwise okay-ish. The screenshot's very much wider than it is tall, so I think we're back in business!

 

[Trash80toHP_Mini]

It's a beautiful thing at TPD resolution! The angle of your shot was a problem and it wasn't readily apparent to me that the vertical scaling had letterboxed it so badly, making it seem extended. Glad you've got it going. I'd be jealous, but I've still got a pair high end 21" color TPDs to go with the gorgeous Portrait Display.

 

[warmech]

Quick update after recapping - it's looking great (excuse the image offset, I didn't realize how far off to the right the desktop was on the screen) and currently breaking in at the moment:

 

[Cory5412]

What a beautiful display, glad to see you were able to get it running!