Synchronous serial Re: E-Mail Formats RE: Future of cctalk/cctech

Antonio Carlini a.carlini at
Thu Jun 18 05:47:22 CDT 2020

On 18/06/2020 10:06, Peter Coghlan via cctalk wrote:
> To get somewhere near back on topic, I am trying to set up a synchronous
> serial link between two MicroVAX 3100 machines with DSH32 (or DST32 maybe)
> interfaces.  One of the options I have is a BC19D cable and a BC19V cable
> which seem to be identical or nearly identical.  Each plugs into a DSH32
> at one end and has a V.24 DB25 connector at the other end.  I don't seem
> to have anything available in the way of a pair of suitably similar modems
> or a modem eliminator to put between the two V.24 connectors.  Can anyone
> suggest some kind of a quick hardware hack that I could use to fill the
> gap?  Is a pair of DB25 sockets with crossed over wiring betweeen them
> sufficient or do I need something that generates clock signals too?

I can't find my DHS32/DST32 docs right now but it's probably a simple 
re-spin of the DSH32.

I think that the DST32 was the uVAX2000 option and the DSH32 was for the 
uVAX 3100 series.

My notes say that my MicroVAX 2000 has a DST32 (54-17230) but the 
preliminary version of EK-283AA-AD-001 is for the DSH32 and that talks 
about the MicroVAX 2000!

I think that in the lab at DEC I used a modem eliminator (I used to 
support all of the synch devices supported by VAX WANDD). I may even 
have some of those modem eliminators in the garage.

Just to double check ... you definitely have synch boards and not (for 
example) 8-way asynch lines? There were a whole bunch of designators 
that were so very close: DST32, DHT32, DSH32, DHW41, DSW41!


Antonio Carlini
antonio at

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