While probably unrelated, the mentioning of 3 rows of pins did remind me about what I recently learned about the 1973 IBM SCAMP...
On the back side of it, it has a 3-row of 14-13-14 female pins (next to what became a DB25 connector - did DEC come up with DB25??). Was curious if anything ideas on what that 3-row might be for. The photo should be here: https://voidstar.blog/scamp-a-review-50-years-later/#jp-carousel-6400 -Steve On Sun, Aug 6, 2023 at 4:35 PM Chuck Guzis via cctalk <cctalk@classiccmp.org> wrote: > On 8/6/23 14:08, Paul Koning via cctalk wrote: > > > > > >> On Aug 4, 2023, at 10:10 PM, Jonathan Chapman via cctalk < > cctalk@classiccmp.org> wrote: > >> > >>> Anyone seen those before, and is it actually SCSI, or is it something > else? > >> > >> Common on old Sun SCSI stuff, it's a DD-50. Could be something else, > but they were indeed used for SCSI termination. > >> > >> Thanks, > >> Jonathan > > > > The D-sub shells come in standard and high density flavors. For all > except the biggest one (DD), standard is two rows and HD is three. But DD > has three rows in the standard density and 4 rows in high density. > > DC62 was used in several tape drive controllers. > > --Chuck > > >