7 Oct
2020
7 Oct
'20
10:32 a.m.
On Wed, Oct 7, 2020 at 12:07 PM Glen Slick via cctalk
<cctalk at classiccmp.org> wrote:
On Wed, Oct 7, 2020 at 8:37 AM Ethan Dicks wrote:
I have very dim memories of that arrangement - it was definitely
ordinary that you had a dedicated I/O processor to run multiple lines.
Part of the salable benefit of the COMBOARD was having an 8MHz 68000
manage the actual protocol - it moved block file data to/from the DEC
host via DMA. The M68K wrapped it up as needed, handled
re-transmission, etc.
Using a KMC11 is similar, IIRC, certainly at the bottom levels.
-ethan
-ethan
On Wed, Oct 7, 2020 at 5:07 AM Peter Allan wrote:
I was curious about this DEC M8704 DMS11-DA that sold cheap a few days
ago. It has eight SMC COM5025 "Multi-Protocol Universal Synchronous
Receiver/Transmitter USYNR/T" chips:
https://www.ebay.com/itm/373243388363
Apparently it can't do anything on its own. It needs to be connected
to a UNIBUS through a companion KMC11 processor board, which might not
be too common if someone wanted to put together a working
configuration. RJE/HASP
2780/3780 Protocol Emulator
I used to do this with specialty hardware...
http://www.bitsavers.org/pdf/softwareResults/Software_Results_Comboard_Broc…
There were also intelligent sync serial engines for this from other
vendors, including DEC (KMC11, and probably a later one but the device
name escapes me).