10 Apr
2024
10 Apr
'24
9:36 p.m.
Glen Slick via cctalk wrote:
On Wed, Apr 10, 2024, 7:22 PM Carlos E Murillo-Sanchez
via cctalk <
cctalk(a)classiccmp.org> wrote:
How interesting, thanks! The knowledge in this
list never ceases to
amaze me.
Carlos.
Jonathan Chapman via cctalk wrote:
That is not an unusual bit slice architecture for a drive controller.
This Dilog DQ419 also has two AM2901 ALUs and three AM2911 sequencers, and
what appears to be six microcode PROMs.
https://avitech.com.au/?page_id=847 > 1. I have read that the card and the drives
were compatible with the
dec rx02 drives. Why would the CRDS even bother to
redesign a card where
DEC had perfectly good working ones? Anyone know if there is any value in
keeping the FC-202 or just keep with the DEC cards?
A lot of the third-party controllers could talk
to Shugart-style 8"
floppy drives. They can also usually *format* the
diskettes, which the
RX01/RX02 systems from DEC can't do -- you have to use preformatted media.
This isn't a *huge* deal since RX01 is just IBM 3740 and you can format it
on CP/M boxes, with ImageDisk, etc. There's an XXDP utility to upconvert
RX01 media to RX02, which is M2FM and very few things can work with it.
Apparently a lot of small shops kept a CP/M box
just for the task, the
Alspa ACI-2 I had was supposedly used like that.
> 2. Any idea on that other card?
https://w2hx.com/?prefix=x/What-Is-It/PDP-11-Thing/Board1/
Looks like a non-DEC Qniverter -- QBus to Unibus
converter. If that's
what it is, you'd plug your Unibus cable into that
pair of connectors on
top and run it to whatever Unibus device you were wanting to talk to,
potentially another backplane full of Unibus stuff. Commonish upgrade on
e.g. CNC machines that were originally controlled by a PDP-11/05 or
something in one Unibus chassis, with another Unibus chassis full of
machine-specific cards.
Thanks,
Jonathan
.
I spy two AM2901 4-bit slice ALUs, two N82S181 1024x8 PROMs, three
AM2911 microprogram sequencers, and an SN74150 3-to-8 line decoder. This
thing is doing arithmetic.
Carlos.