I don't know about the model 25, but we had a room full of mod 30s that had a locally MODIFIED operating system (DOS) to support a program we called COS or COSFG (for compatibility operating system), so we could emulate two 1401s (each an 8K 1401 in a 24K DOS paritition), one in the F1 partition and one in the BG partition, each with its own card reader running DOS jobs (starting with release 18(?) of DOS (prior to that there was no job control system for the F1 F2 parititions. The F2 partition was only 2K and had to be started by console commands (JCL required a 12K (?) partition, and we used it for spooling, mostly printing tapes created on the 7010s, but a few programs we ran on the mod 30s also spooled input or output. And once a year we had to copy all the source program card decks onto tape for offsite backup.
Each mod 30 had a 2540 card read/punch, a 2501, two printers (usually a 1403N1 and a 1404 or 1403), three to five 2311 disk drives, and maybe four or five 2401 tape drives. On disk 190 was the operating system, the others were not used except fro sort work areas and a very small number of native 260 programs. Later on they added 2520 card punches to some systems so both foreground and background could punch cards. On first shift, there were two operators per machine, one for F1 and one for BG normally, but also to cover breaks/lunch and F2. Off shift and weekends, only one person per machine, you would try to keep both partitions busy (jobs did tend to be longer), but if you couldn't, you didn't need to worry about it. Most jobs only had to be done by morning anyway, but during the day jobs would come in and be picked up in minutes or hours. On 11/7/06, Bob Shair <[EMAIL PROTECTED]> wrote:
At 04:05 PM 11/7/2006, you wrote: ...Microcode was available to make the -25 emulate a full 360, a 1401, or (I think) a -20. Concurrent operation in different modes was not available, but it could certainly run DOS. ...
-- --Carey
