Two configuration words are required for
control of the diskette (see Figure 5-6). Con
figuration Words A and B contain the image of
CONFIGURATION WORD A
CONFIGURATION WORD B
Figure 5-6. Configuration Words A and B
the ID field of the sector on which a particular
operation is initiated. The track number in
Configuration Word A (bits 0-7) is used as the
seek argument for seek operations. The sector
number field of Configuration Word B (bits 0-7)
are incremented after each data field during
update read or write operations and will point
numerically to the next sector after completion
of the operation. Bits 8-15 of Configuration
Words A and B are Reserved for Software Use
(RSU). IBM formatted diskettes will have zeroes
in these fields.
Diskette operation is implemented by two sets
of instructions; the input and the output com
mands (see Table 5-2). A discussion of these
TABLE 5-2. COMMAND REPERTOIRE
IOLD (Output Address and Range)
Output Interrupt Control
Output Configuration Word
Output Configuration Word B
Input Interrupt Control
Input Configuration Word A
Input Configuration Word B
Input Device - Identification
IFor the diskette, the device number is 2010 (HEX)
commands will be found in the Series 60 (Level
6) Minicomputer Handbook, Order No. AS22.
Prior to powering-up the diskette, it is as
sumed that all electrical cables have been properly
connected and secured. Power is supplied or
removed from the diskette by the power ON/OFF
switch located on the front panel of the device
(see Figure 5-7). Setting the switch to ON
supplies the power required to operate the device.
The power indicator will illuminate indicating
that power is available. Setting the switch to the
OFF position removes power from the device and
extinguishes the indicator.
Prior to mounting, visually check the condi
tion of the disk. It should not be torn, folded or
creased. Avoid using a damaged disk.
1. Should the diskette be located within a
cabinet, slide the unit out of the cabinet.
2. Press the access cover button on the disk
ette (see Figure 5-7) and carefully place the
disk package directly over the spindle.
3. With the disk firmly seated on the spindle,
close the diskette cover and slide the unit
back into the cabinet (should the device be
located in a system cabinet).
4. The diskette spindle automatically engages
the disk and the device is ready for
Remove the disk package according to the
procedures described in mounting a disk.
Operator maintenance is the preventive main
tenance required by an operator in maintaining
proper operation of the diskette. Preventive main
tenance includes the checks, cleaning, operating
habits, etc., done periodically on a scheduled
basis, even though diskette operation may be
satisfactory and not in need of attention.
Care And Handling Of Disks
The following routine rules are the prerequi
sites for proper disk handling and storage.