122 Disk Crossover and Controller circuit packs
297-1001-536 Standard 01.03 August 1996
Table 13–2
xxx
Disk controller circuit pack (A21A1) options – part number: 680–9143
Device type
(number)
Position/setting
Function
Setting
Factory On–site
Jumper
(W0)
0
1
2
3
4
5
6
7
State
Pri.
shorted; I.D. = 0
shorted; I.D. = 1
shorted; I.D. = 2
shorted; I.D. = 3
shorted; I.D. = 4
shorted; I.D. = 5
shorted; I.D. = 6
shorted; I.D. = 7
SCSI Controller ID.
Defines the SCSI
device priority. ID 7 is
the highest priority in a
multi–controller
configuration.
0
Must be
the same
as the
factory
setting.
Jumper
(W1)
1
2
– 2 = parity enabled
– 3 = parity disabled
Host Parity
1–2
Must be
the same
as the
factory
setting.
Jumper
(W2)
Not used
Jumper
(W3)
(W4)
W3
W4
Bytes Per
Sector
open
open
128
short
open
256
open
short
512
short
short
1024
Select disk drive
Sector Size
W3
open
W4
short
Must be
the same
as the
factory
setting.
Jumper
(W5)
(W6)
(W7)
(W8)
Function established in the
copper tracings; do not modify
Logical Unit Number
Assignment.
Out
Out
Out
Out
Must be
the same
as the
factory
setting.
Strap
None used
DIP
Switch
None used
Rotary
Switch
None used
Switch
None used
Note:
Note 1: There are no customer–definable options on this circuit pack. Information is for reference only.
Note 2: Only present on the 72–Mbyte and 140–Mbyte disk drives.
