IBM System/360 Field Engineering Manual

2841 STORAGE CONTROL (Continued)
Seek Address
Cell Number
Cylinder Number Head Number
Type
Byte 0 Byte 1 Byte 2
Byte 3 Byte 4 Byte 5
2311
0 0 0 0-202
0
0-9
2302 Models 3 and 4
0 0
0 0-249
0
0-45
2303
0 0
0
0-79
0
0-9
2321
0 0-9 0-19 0-9
0-4
0-19
Subcell Strip Bar
Head No.
2314
0 0
0 0-202
0
0-19
File Protection
The significance of the file mask bits is:
BO Bl
0 Inhibit Write Homi~ Address and Write RO
Inhibit !!! write commands
Inhibit Write Home Address - Inhibit Write RO - Inhibit Write
Count, Key, and Data
Permit all write commands
B3 B4
0 0 Permit all seek and restore commands
Permit Seek CCHH and HH CCWs
Permit Seek HH CCW
Inhibit ~ seek commands
B2 B5 B6 B7
0 0
Attention Not Used
Status Modifier Used with Search and Control Unit Busy.
Control Unit End The control unit has finished an operation.
Busy Indicates addressed access mechanism is moving;
or used in conjunction with Status Modifier to
indicate Control Unit Busy.
Channel End The control unit has received all the data from the
channel needed to do the operation called for and
the channel is freed.
Device End
Unit Check
Unit Exception
IBM CONFIDENTIAL
Indicates that an access mechanism is free to be
used.
Indicates that a control unit or programming
error or device hardware check has been detected.
End-of-File.
S/360 93

IBM System/360 Specifications

General

Brand	IBM
Model	System/360
Category	Desktop
Language	English