3
4.9
12875A Processor Interconnect......................................................................................................53
4.10 12920A Asynchronous Multiplexer Interface ................................................................................56
4.10.1 Lower and Upper Data PCAs...................................................................................................56
4.10.2 Control PCA.............................................................................................................................60
4.11 12966A Buffered Asynchronous Communications Interface.........................................................61
5Programmed Disc I/O Device Simulations ....................................................................................65
5.1
12557A Cartridge Disc Interface with Four 2870 Drives, 13210A Disc Drive Interface with Four
7900 Drives.....................................................................................................................................65
5.2
12565A Disc Interface with Two 2883 Drives...............................................................................67
5.3
12606B Disc Memory Interface with One 2770/2771 Disc, 12610B Drum Memory Interface with
One 2773/2774/2775 Drum ............................................................................................................70
5.4
12821A Disc Interface with Four 7906H/7920H/7925H Drives....................................................72
5.4.1
Device Options.........................................................................................................................73
5.4.2
Unit Options .............................................................................................................................74
5.4.3
Tracing and Registers...............................................................................................................75
5.5
13175D Disc Controller Interface with Eight 7905/7906/7920/7925 Drives.................................76
5.5.1
Device Options.........................................................................................................................77
5.5.2
Unit Options .............................................................................................................................77
5.5.3
BOOT command ......................................................................................................................78
5.5.4
Tracing and Registers...............................................................................................................78
6
Programmed Magnetic Tape I/O Device Simulations....................................................................81
6.1
12559C 9-Track Magnetic Tape Unit Interface with One 3030 Drive...........................................81
6.2
13181B Digital Magnetic Tape Unit Interface with Four 7970B Drives, 13183B Digital Magnetic
Tape Unit Interface with Four 7970E Drives .................................................................................82
6.2.1
Device Options.........................................................................................................................83
6.2.2
Unit Options .............................................................................................................................84
6.2.3
BOOT Command .....................................................................................................................84
6.2.4
Tracing and Registers...............................................................................................................85
