4 Dec
2004
4 Dec
'04
10:16 p.m.
On Sat, 2004-12-04 at 16:13, Paul Koning wrote:
The simplest protocol has to be Burroughs Standard Poll Select. Imagine
daisy-chained RS232 and a polling sync or async protcol using ascii
control characters/words. I did lots of conversions to frame relay using
Motorola routers with Poll Select.
>>>> "Bj??rn" == Bj??rn <bv(a)norbionics.com> writes:
Bj??rn> IBM 3270 used the EBCDIC control codes for their documented
Bj??rn> purpose. HP 2645 terminals had an option to run multidropped
Bj??rn> using an almost identical protocol. This protocol is half
Bj??rn> duplex.
That brings back some nightmares... the ugliest protocol by far I ever
worked on was the one used by Harris 2200 newspaper display editing
terminals. Bisync, half duplex, multidrop, using a PDP-11 DL11-E
async line at the host end. Bletch. Naturally, the driver would mess
up only during the midnight to 6 am shift... and I got to debug it
while the composing room foreman was waiting for things to be put back
into working order.