Diskette Drives; Keylock Feature - IBM 5280 Technical Newsletter

ATTACHMENTS AND FEATURES
Diskette Drives
The IBM 5280 system uses two types of diskette drives: the
31S0 and the 51TO. The 31S0 diskette drive uses only the
type 1 diskette. The 51 TO diskette drive uses the type 1
diskette, the type 2 diskette, and the type 20 diskette. Data
is recorded only on one side of the type 1 diskette and on
both sides of the type 2 diskette and the type 20 diskette.
Each IBM 5280 system requires a minimum of one diskette
drive.
The following chart shows the capacities of the diskette
types that can be used on the IBM 5280 system.
Physical
Record
Diskette
Length
Type in Bytes
Diskette 1 128
Diskette 1 256
Diskette 1 512
Diskette 2 128
Diskette 2 256
Diskette 2 512
Diskette 20 256
Diskette 20 512
Diskette 20 1024
Total Storage
in Bytes
246272
284160
303104
492544
568320
606208
985088
1136640
1212416
Exchange
Type
Basic and I
Basic and I
H
and I
Printers
Page of SY31-0600-1
As updated April 15. 1981
By TNL SN20-9588
The IBM 5280 system can use either the IBM 5222 Ser.ial
Matrix Printer, the IBM 5224 Line Printer, the IBM 5256
Serial Matrix Printer, or the IBM 5225 Line Printer. All of
these printers except the IBM 5222 are attached to the IBM
5280 by twinaxial cable. The IBM 5222 is attached to the
IBM 5280 by start-stop cable. One printer can be attached
to the IBM 5285 and up to eight printers can be
attached to the IBM 5288. .
Keylock Feature
The keylock feature provides data security on the IBM 5280
system. It is a key-operated switch that can be instalied on
the programmable units only. The switch has three positions:
local, normal, and lock. One key is required to move the
switch from the lock position to the normal position and a
different key is required to move the switch from the lock
position to the local position. The key cannot be removed
from the switch in the local position or the normal position
but can be removed in the lock position.
When the switch is in the local position, communications
cannot be established. If the system is in communications
mode when the switch is placed in the local position,
communications proceed normally until the end of the
current job.
When the switch is in the normal position, communications
can be established and maintained.
When the switch is in the lock position, commLmications
cannot be established. If the system is in communications
mode when the switch is placed in the lock position, com-
munications proceed normally until the end of the job.
Howeve~,
in the lock position, all keyboards are disabled,
and no image can be displayed on the screen.
Introduction 243