>I've been watching this thread with some interest, as I'm curious how large
>a board with 512Kbytes in 4116's would be. I've got some boards downstairs
>which have sites for 288 4116's on each. That's 576KB, though it's
>organized as 64-bit words with off-board SECDED which makes it 512 KBytes
>with correction. These boards are about 15"x22" which is quite a bit large
>for any of my S-100 boxes. The compupro boys often were fairly ambitious
>with their "features" and may have planned a different
>jumpering/multiplexing scheme for the power, addresses, etc, which were
>different once the 64K parts became available. However, considering what it
>took to make a memory board, even 64K parts would have left it a difficult
>task to fit all those DRAMs on the board, considering 1982 or so technology.
The M-Drive/H 512K's that I have are populated with 64 4164's (1982/1983
date codes) and the M-Drive/H 2MEG's that I have are populated with
64 41256's (1984 date codes). The DRAM's take up about 70% of the board,
with the remainder going to the Intel DRAM controller (8203), bus drivers,
PAL's, and regulators.
These boards were available partially populated, too.
These boards were not cheap when introduced; from old price lists,
they sold in the $5000-$8000 range fully populated.
> The Godbout boys were really
>not inclined to use the most costly technology available. Hence, I doubt
>the CompuPro board in question held 512K of 4116's.
I agree, it wouldn't be physically possible to put 512K of 4116's on a
single S100 board. But the Compupro folks had customers who were more
than willing to buy a S-100 board the price of a new car, and bought
the technology to do it with the denser DRAM's just becoming widely
available at the time.
--
Tim Shoppa Email: shoppa_at_trailing-edge.com
Trailing Edge Technology WWW: http://www.trailing-edge.com/
7328 Bradley Blvd Voice: 301-767-5917
Bethesda, MD, USA 20817 Fax: 301-767-5927
Received on Thu Jun 24 1999 - 07:37:07 BST