11 Sep
2022
11 Sep
'22
3:40 a.m.
On 2022-09-11 03:36, Robert Armstrong wrote:
RSX does too, but not so sure about any other DEC OS.
Dave McGuire
<mcguire(a)neurotica.com> wrote:
But what about DECnet over async?
Not sure that TOPS-10 supports async DECnet. VMS does, but I don't know
about TOPS-10. And even if it does, the 2020 only supports a DZ11
terminal interface,
which is a character by character interrupt device (i.e. no silo). Given
that and the limited UBA bandwidth in the KS10, I don't think it would be a
good idea.
Yeah. It's actually a pretty horrible idea. RSX have drivers for running
async DDCMP over DZ, but it's definitely one of those "if you have
anything else, you should probably use that".
However, the DZ do have SILOs. Otherwise it would run a high risk of
loosing characters. But it's still lots of input interrupts. But that's
not the really bad thing. Most (if not all) DEC serial line interfaces
do lots of interrupts on input. However, the DZ does it also on output,
which is the horrible part. Other interfaces, such as the DH does DMA
for output, which obviously is *way* better.
Johnny
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|| on a psychedelic trip
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