AST Six Pak Plus

[modem7]

Anyone have any information on an 8-bit Quadram Memory card? (Its a memory only card no other functions)

The card has three horizontal memory sockets and 1 set of
Dip Switches numbered 1-8.

Basically I need to know what the settings are and what kind of memory chips this thing requires.

Will memory from an AST 6-Pack work on it?

I think I might have the same card. On mine, "QUADRAM CORP" in lower-left corner on component side. U33 to U41 along bottom of card. "SHORT RAM" on a label on U28, and on the sticker on rear of board. Does that sound like the same card?

 

[gerrydoire]

I think I might have the same card. On mine, "QUADRAM CORP" in lower-left corner on component side. U33 to U41 along bottom of card. "SHORT RAM" on a label on U28, and on the sticker on rear of board. Does that sound like the same card?

Same Card, you have configuration info for the card?

 

[modem7]

Same Card, you have configuration info for the card?

I'll see if I can find a manual.

Presently, I can tell you that my card is populated with D41256C-15 RAM chips, and SW1 is set to 11011010. As I have not plugged that card into a PC, I'm unsure of the starting address that that setting of SW1 corresponds to. I guess that some of the switches on SW1 may reflect the number of rows of RAM that are populated.

 

[modem7]

Quadram short ram

Quadram short ram

I was unable to find a manual.

I did find a manual for a MEMO 576 card which is very similar - same physical size, 8 bit, three rows of RAM, one switch block of 8 switches, similar component count. The switch block on it is adjusted for:
* starting address
* whether the RAM chips are 64K or 256K (or certain combinations)
* parity checking on/off
* a switch that must be in the on position
* 2 unused switches

I expect the Quadram card to be similar.

What I failed to state about my Quadram card is that only one row is populated and I do not know the history of the card. It may even be faulty because so far, I can't get it to work, even if I add extra RAM chips (of either 64K or 256K).

If dongfeng's card is indeed the same card (filled with 64K chips), we need him to tell us what the switch settings are on his card and the corresponding starting address.

 

[patscc]

Quadram Quadboard settings

Quadram Quadboard settings

Take a look at the attached zipped pdf, though I think it's a different board than then one from your description.
It takes 4164 type dram. As far as I know, it does not support 41256 chips.
If your takes 41256 chips, you still might be able to use the jumper settings and a bit of fiddling.
Hope this helps

 

[gerrydoire]

Take a look at the attached zipped pdf, though I think it's a different board than then one from your description.
It takes 4164 type dram. As far as I know, it does not support 41256 chips.
If your takes 41256 chips, you still might be able to use the jumper settings and a bit of fiddling.
Hope this helps

With 3 rows of 9 sockets, if this card takes the 41256, how much memory would that equal.

 

[gerrydoire]

I was unable to find a manual.

I did find a manual for a MEMO 576 card which is very similar - same physical size, 8 bit, three rows of RAM, one switch block of 8 switches, similar component count. The switch block on it is adjusted for:
* starting address
* whether the RAM chips are 64K or 256K (or certain combinations)
* parity checking on/off
* a switch that must be in the on position
* 2 unused switches

I expect the Quadram card to be similar.

What I failed to state about my Quadram card is that only one row is populated and I do not know the history of the card. It may even be faulty because so far, I can't get it to work, even if I add extra RAM chips (of either 64K or 256K).

If dongfeng's card is indeed the same card (filled with 64K chips), we need him to tell us what the switch settings are on his card and the corresponding starting address.

Can you scan the dip switch settings for me to see?

 

[patscc]

3 * 256

3 * 256

768 kByte

Seriously, though, before I get slapped, the 4164 has a N/C at pin one, on a 41256 this is A8.
In theory, if it's a 4164 board, pin one should not connect to anything. If pin one looks like it gets routed the to the pc's address bus, perhaps via some latches or what not, then it takes 41256 chips, or a mix of 4164 & 41256.

Not to point out the obvious, the organization of the chips is either 64k x 1 or 256k x 1 per column.. The ninth row is for the ever-popular parity.

patscc

 

[gerrydoire]

768 kByte

Seriously, though, before I get slapped, the 4164 has a N/C at pin one, on a 41256 this is A8.
In theory, if it's a 4164 board, pin one should not connect to anything. If pin one looks like it gets routed the to the pc's address bus, perhaps via some latches or what not, then it takes 41256 chips, or a mix of 4164 & 41256.

Not to point out the obvious, the organization of the chips is either 64k x 1 or 256k x 1 per column.. The ninth row is for the ever-popular parity.

patscc

The card will take 41256, the guy who sold it to me stated it was a 768 memory board, that is if he knows what he is talking about...

 

[modem7]

The card will take 41256, the guy who sold it to me stated it was a 768 memory board, that is if he knows what he is talking about...

These simple RAM cards just top up motherboard RAM. So assuming the worst case of a 16/64KB 5150 motherboard with 16 KB fitted, the most you'd expect such a card to provide is 624 KB (640-16=624).

The MEMO 576 card I quoted earlier supports a maximum of 576 KB (as two banks of 256 Kbit chips and one bank of 64 Kbit chips).
So like the MEMO 576, I expect that the Quadram Short RAM card supports varying combinations of 256 Kbit and 64 Kbit chips (setting the card's switch settings accordingly).

Can you scan the dip switch settings for me to see?

Yes, I'll do that, but note that the current switch settings on my Quadram Short RAM card don't appear to match the settings in the MEMO 576 manual.

 

[patscc]

hma

hma

modem7 said... 624 KB (640-16=624).

I seem to remember you could push it up to 704k if you didn't use cga and had 768 k.
Although now I can't remember if this worked on the pc, or only on the xt and higher.

patscc

 

[MikeS]

The extra memory could usually be used for a RAM disk or print spooler; Quadram supplied a suite of utilities (QuadMaster) for that purpose.

 

[modem7]

Note that I used, "These simple RAM cards just top up motherboard RAM", with the key word being "simple".
By "simple", I'm speaking of RAM cards where all the support chips do is basically address decoding.

More advanced cards will have their own pool of RAM which can be used for various purposes (RAM top up, expanded memory, print spooler, etc.)
That requires extra circuitry.

The MEMO576 is a "simple" RAM card, and when I look at the Quadram Short RAM card, I see an almost identical card.

Can you scan the dip switch settings for me to see?

At http://members.dodo.com.au/~slappanel555/manuals.htm

 

[modem7]

I seem to remember you could push it up to 704k if you didn't use cga and had 768 k.
Although now I can't remember if this worked on the pc, or only on the xt and higher.

From what I've read, with a (standard) monochrome video card, up to the 704 KB mark is available to be mapped. With a (standard) CGA video card, up to the 736 KB mark is available to be mapped.

In reference to what I describe as "simple" RAM cards:

The manufacturer has the option of supporting 64 Kbit and 256 Kbit RAM chips. To get 128 Kbit chips, they would have had to go the route that IBM did on the early 5170 motherboard - piggybacked 64 Kbit chips - something not desirable (expense, card width, etc.).

So if you look at a "simple" RAM card such as the MEMO576, if the manufacturer supported a configuration of three banks of 256 Kbit chips, that would result in a total of 768 KB of contiguous RAM. As for starting address, when I think about it now, the actual worst case is a clone motherboard with all RAM socketed, and so with all RAM removed on such a motherboard, the starting address for the RAM card is 0. And so such a combination results in RAM from 0 to 768 KB, which spills into the CGA address space.
I'm sure that will be why the makers of the "simple" MEMO576 chose a maximum of two banks of 256 Kbit + one bank of 64 Kbit (rather than three banks of 256 Kbit). I think the Quadram Short RAM card will turn out to be the same.

 

[gerrydoire]

Note that I used, "These simple RAM cards just top up motherboard RAM", with the key word being "simple".
By "simple", I'm speaking of RAM cards where all the support chips do is basically address decoding.

More advanced cards will have their own pool of RAM which can be used for various purposes (RAM top up, expanded memory, print spooler, etc.)
That requires extra circuitry.

The MEMO576 is a "simple" RAM card, and when I look at the Quadram Short RAM card, I see an almost identical card.


At http://members.dodo.com.au/~slappanel555/manuals.htm

Thanks for the memories...

 

[Terry Yager]

Another exception is the Kaypro board I'm looking at right now, which is a true 768Kb board, but the Kaypro is a strange beast by XT standards. 16-bit Kaypros were straight backplane systems, so all of the memory is on a daughter board. In the Kaypro, it uses the 'extra' 128 as a RAMdisk. When installed in a 'normal' XT, it only sees up to the 640K boundary, although there may be software somewhere to use the extra RAM, I've never researched it. This board was most recently used in my 5155, but only to fill-out the 384K missing from the XT mainboard.

--T

 

[patscc]

ramdisk

ramdisk

Terry Yager said...'normal' XT, it only sees up to the 640K boundary

There's something out there called Turdodsk that I think would let you stuff a RAM disk in there.
patscc

 

[MikeS]

So if you look at a "simple" RAM card such as the MEMO576, if the manufacturer supported a configuration of three banks of 256 Kbit chips, that would result in a total of 768 KB of contiguous RAM. As for starting address, when I think about it now, the actual worst case is a clone motherboard with all RAM socketed, and so with all RAM removed on such a motherboard, the starting address for the RAM card is 0. And so such a combination results in RAM from 0 to 768 KB, which spills into the CGA address space.
I'm sure that will be why the makers of the "simple" MEMO576 chose a maximum of two banks of 256 Kbit + one bank of 64 Kbit (rather than three banks of 256 Kbit). I think the Quadram Short RAM card will turn out to be the same.

--------
Maybe...

But I'm looking at the manual for the Quadram Quadboard II which is an 8-bit PC card with up to 4 banks of 64K ea.; it can be located starting on any 64K boundary from 64K to 960K and comes with software for both a RAM disk and a print spooler...

 

[modem7]

--------
Maybe...

But I'm looking at the manual for the Quadram Quadboard II which is an 8-bit PC card with up to 4 banks of 64K ea.; it can be located starting on any 64K boundary from 64K to 960K and comes with software for both a RAM disk and a print spooler...

Sounds like it's not far removed from the original Quadboard, which is another "simple" card.

If it's like the original Quadboard, Quadram have devoted 4 switches for the 'starting address' functionality.
That's good because if you already have 640KB of RAM and have a (standard) monochrome or CGA card, you could use Quadboard fitted with 64KB of RAM, set to a starting address of 640K, to put RAM into the 640K to 704K area. A starting addresses of 960K is useless (conflicts with ROM BIOS).

If the Quadboard II is like the original Quadboard, Quadram are doing nothing special to get the RAM disk. The software convinces DOS that there is less total RAM in the system than there actually is, then the software uses the RAM that DOS doesn't believe is there. That trick can be done even if only motherboard RAM is present.

The print spooler software probably works in the same manner.

 

[MikeS]

It seems that you're absolutely correct; I assumed that since you could address it above 704K you could actually use it, but I guess those addresses are only available because they needed a fourth DIP switch to get above 512K. And unless you have a Quadboard AT that lets you use extended or expanded memory, it looks like the RAMdisk and spooler do indeed use conventional memory; I didn't notice that the utility disk has three different versions, and just assumed that it used a system like the Juko boards that *can* use the unavailable memory for a RAMdisk.

Live & learn...