ps2...@yahoo.com (Ed Gould) writes: > Lyn: > > I bow to your expertize and have not read your paper on the 3725. > > My sort of well lets say home grown experience with trial and error (sigh a > lot > of errorr). > Gut instinct said the limiting factor was the byte channel (which I > understood) > was the vast majority of channel hook ups for the box.
re: http://www.garlic.com/~lynn/2011e.html#31 "Social Security Confronts IT Obsolescence" http://www.garlic.com/~lynn/2011e.html#35 junking CKD; was "Social Security Confronts IT Obsolescence" http://www.garlic.com/~lynn/2011e.html#37 junking CKD; was "Social Security Confronts IT Obsolescence" you must have strayed from the archived ckd/eckd posts into archived sna/vtam misinformation thread (in a.f.c. newsgroup): http://www.garlic.com/~lynn/2011e.html#32 SNA/VTAM Misinformation http://www.garlic.com/~lynn/2011e.html#34 SNA/VTAM Misinformation the above also references more in (linkedin) "Greater IBM" group thread. note that in the above ... series/1 NCP emulation involved a channel interface board that attached to mainframe on same exact channel as 3725 and appeared to the mainframe exactly as a 3725 (slight of hand was that it told all the mainframes that resources were cross-domain ... "owned" by somebody else). Since the interface board and channel appeared identical ... then any related limitation was identical for 3725 and series/1. slight topic drift ... long ago and far away ... there was an internal effort to convince the communication group to use "peachtree" (processor for series/1) as being significantly more capable than the processor chosen for 37x5. additional topic drift ... even longer ago, as undergraduate in the 60s ... i added tty/ascii terminal support to cp67. cp67 had 1052 & 2741 support with fancy automatic terminal recognition ... fancy use of 2702 SAD command to re-associate different line-scanner to port. I then intergrated TTY/ASCII ... supporting automatic terminal identification (and re-associating different line-scanner with 2702 SAD command). It worked fine for leased line ... but i wanted to do single dial-up phone number (& hunt group) for all dial-up terminals ... where it broke. While 2702 allowed changing line-scanner on port ... 2702 took shortcut and hardwired oscillator/line-speed on each port. This was somewhat the motivation for the univ. to start clone controller project, reverse engineering mainframe channel interface, building mainframe channel board for interdata/3 and programming interdate/3 to simulate 2702 ... but also doing automatic line-speed operation. four of us get written up as being responsible for (some part of) clone controller business ... misc. past posts http://www.garlic.com/~lynn/subtopic.html#360pcm decade or so ago, was in large datacenter with a many generation descendent of that box handling large percentage of dial-up POS cardswipe terminals in the country ... claim was that the channel interface board hadn't changed ... although it was a many times descendent of interdate/3 (including name change when perkin/elmer bought interdata). -- virtualization experience starting Jan1968, online at home since Mar1970 ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
