On Wed, Apr 10, 2024, 7:22 PM Carlos E Murillo-Sanchez via cctalk < cctalk@classiccmp.org> wrote:
> Jonathan Chapman via cctalk wrote: > >> 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. 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
