Thomas Berg wrote on 11/11/2011 6:37 AM:
About the 2250, a link with a photo of the wonder in action: http://www.columbia.edu/cu/computinghistory/2250.html
The text on that page mentions using it as the console on a 360/91. UCLA CCN had such a thing. The 2250 was the master console and was used only for IPL, unless we lost the flaky controller driving the rest of the consoles (12x40 CCI terminals which were probably knock-offs of IBM 2260-1.) Otherwise the 2250 was ignored because of the keyboard which could most charitably be described as clunky, even by 1973 standards. It was the same mechanical key-interlock keyboard as on the 2741 (?), where pressing a key pushed a bunch of machinery around inside the keyboard to prevent you from pressing two keys at once. Hideously slow to type on. And the screen flicker could drive you batty.
The 2250 MCS console support was flaky; I once crashed something (38 years later I can't remember if it was just the 2250 or all of MVT) by idly clicking the light pen aimed at the fluorescent lights in the ceiling. Interestingly enough, MVT supported using the light pen to click on the MCS console for the functions of "K D,F" and "K E,D", and I have a really vague recollection that there were numbers you could click on for the equivalent of PFK-assigned commands.
Rick Fochtman wrote on 11/11/2011 3:47 PM:
IIRC, the 2250 was a vector-graphics tube requiring GAM to fully exploit.
Or, get this, OLTSEP, the OnLine Test Standalone Executive Program, i.e., the IPLable version of OLTEP. As a student part-time operator working weekend shifts, I got to run OLTSEP occasionally during Sunday Preventive Maintenance. Someone really went hog wild programming OLTSEP to run on the 2250 -- it used many different character sizes and I think some limited graphics and the light pen. It was the only time I ever saw the 2250 do something other than an MCS console with basic characters in a single size.
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