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General porpoise IO cards, and cheapest ROM solution for Qbus (the bus, not the user)

Christoffer

Experienced Member
Joined
Oct 15, 2014
Messages
299
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Denmark
Hi! I've been pondering some questions in the last months of making my 11/23 do stuff. And while getting a FDD running looks promising, I still have to punch in a bootloader via terminal or PDP11GUI. "I have no ROM, and I must boot", as Harlan Ellison wrote.

Now, the "original" solution would be a BDV11 card, with 18 2716 sockets for boot memory, but they're pretty rare, and when they pop up, they're not cheap. Are there any other bootable ROM cards to look for? DEC or otherwise?
I've also thought about getting a QBUS wire-wrap card and make one myself, but it might be a lot of trouble.

The other thing is general porpoise IO. The PDP11's (especially the LSI systems) was and is very very broadly used in the industry/industrial control kinda scene. Are there general porpose boards for I/O, like, non-specific boards for driving relays, sensors, etc.? It'd make sense, but there's a bit less structure in the info about third-party pdp11 cards.

Cheers
 

MattisLind

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Joined
Sep 30, 2013
Messages
898
Location
Stockholm, Sweden
Now, the "original" solution would be a BDV11 card, with 18 2716 sockets for boot memory, but they're pretty rare, and when they pop up, they're not cheap. Are there any other bootable ROM cards to look for? DEC or otherwise?
I've also thought about getting a QBUS wire-wrap card and make one myself, but it might be a lot of trouble.

REV11 is a simple card that looks like the M9312 for the Unibus. But it only takes old bipolar PROMs. Then there are the MXV11 card. Combo cards with RAM, ROM and dual SLUs.
The other thing is general porpoise IO. The PDP11's (especially the LSI systems) was and is very very broadly used in the industry/industrial control kinda scene. Are there general porpose boards for I/O, like, non-specific boards for driving relays, sensors, etc.? It'd make sense, but there's a bit less structure in the info about third-party pdp11 cards.

Cheers
The DRV11 spring to my mind. 16 bit parallell I/O.
 

glitch

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Feb 1, 2010
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Central VA
There are a bunch of different UV EPROM cards for the QBus, but almost all of them are expensive. Many are harder to find or more expensive than the BDV11, too. The BDV11 also gives you the flexibility to use a number of ROM sets, including the PDP-11/23+ ROMs which give a very nice hardware self-test and MSCP boot capability.

If you absolutely, positively can't find a BDV11 or similar and want/need one, I do have a spare from my MINC-23 ROM upgrade. I'd been keeping it around since I've got another BDV11 loaded up with the PDP-11/23+ ROMs but wanted to be able to swap back and forth with the MINC's original boot ROMs. Also potentially this is something I/we can lay out and have produced, since it seems people always need BDV11s to cobble a system together. Should be easy to put on a dual-width card with modern ROMs.

The DRV11 spring to my mind. 16 bit parallell I/O.

It's also cheap, as no one seems to want it! Very easy to program. You'll want the documentation in the LSI handbook, most of the DRV11 documentation you find in standalone format is for the DMA-capable version.
 

Mal

Experienced Member
Joined
Apr 3, 2008
Messages
91
Another option is to use a third-party peripheral controller that has an autoboot feature. One that I quite like is the Dilog DQ419 -> http://avitech.com.au/?page_id=847 Once you have booted via floppy you can of course boot other devices from there. Not as nice as having an interactive boot menu, but better than nothing. I haven't tried it yet, but it should be possible to connect up the DQ419 to 5.25" HD drives or to 3.5" HD drives (if they are capable of speeding up to 360RPM). They won't plug in directly of course - you'd need to map the DQ419's 50-way connector to the 34-way connector used on the other drives, and make a few other changes (eg tie the motor-on signal low). There are similar third-party floppy disk controllers designed to work with 5.25" drives (from memory I think one is the MXV50).
 

Christoffer

Experienced Member
Joined
Oct 15, 2014
Messages
299
Location
Denmark
Thanks for the replies! yeah, the DRV11's likely what I'm looking for, in the GPIO department.
No doubt the BDV11'd be the best choice. The MXV11 ram/rom/2xserial looks interesting, especially for potentially make a tiny 2-board pdp11.
Glitch: Laying out a slightly modernized rom card could be interesting. There also don't seem to be too many modern made qbus cards..

Strange how the BDV11's seem to be in shorter supply than a lot of other LSI-11 boards. One'd think there had to be atleast one per 11/03, 11/23, 11/23+, and rom cards for most other embedded lsi-11 systems..

Mal: I do have a FDD that will probably auto-boot (not sure, actually), RQDX2, but I'm still working on a 3,5'' fdd interface..
 

glitch

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4,964
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I would guess that the number of QBus CPU and RAM cards greatly exceeds the number of BDV11 ROM boards due to embedded applications often using custom hardware which could include a bootstrap ROM, or just using one of the bipolar PROM options from DEC. I've got a *ton* of bipolar PROM QBus boards that came out of some sort of industrial control application; unfortunately, I believe they're just straight memory, not the switchable 256-byte window that BDV11 and compatible provide.

I'll look at what laying out a ROM board will take. Probably should include the diagnostic features of the BDV11 as well. Anyone have a source for DEC handles? :)
 

glitch

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