The answer to the question about the DB-25 connector (and others) can be found here, if one trusts Wikipedia. https://en.wikipedia.org/wiki/D-subminiature
No, DEC did not invent it, Cannon did. —Milo > On Aug 11, 2023, at 2:06 PM, Steve Lewis via cctalk <cctalk@classiccmp.org> > wrote: > > 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 >> >> >>