29 Jan
2022
29 Jan
'22
12:58 p.m.
From: Paul Koning
DH-11 is unusual in that it has DMA in both directions
McNamara's DH11? (I don't know of another DECdevice of that name.) Per:
http://www.bitsavers.org/pdf/dec/unibus/EK-ODH11-OP-002_DH11_Asynchronous_1…
it's DMA on output only; the input side has a FIFO that has to be emptied by the CPU.
Noel
PS: I am familiar with the term 'terminal concentrator' from the networking
world, but as a generic term, not the name of a particular product. (Although
Cisco's first boxes may have included a terminal concentrator, so named.)
Noel