On Thu, 16 May 2019 at 12:50, Alan Altmark <alan_altm...@us.ibm.com> wrote:
> Disk, tape, and unit record devices of the same era had discrete > controllers. Unit record CU (2821) was interesting in that it talked to > devices that did different things: 1403/1404 printer and 2540 card > reader-punch. Clever of them. > Another way to think of the 2821 is as a bridge between "modern" (S/360) channel protocols, and "legacy" (1401-style) devices like the 1403 printer. Tony H. ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
