A.3 System Configuration Table
Table A–8 Error Checking and Correcting Bit Descriptions
Name
Description
SUBS
The following is a breakdown of the SUBS field:
•
Bit 3:0 — drive # being replaced
0 = none
1 . . . 9 = drive 1 . . . 9
•
Bit 7:4 — Reserved
DSBL
Field defining which drive is inoperable. If nonzero, do not write
this byte. After writing this byte, run a MOUNTBANK command to
reestablish the active bank. This byte is automatically reset to 0s after
a new replacement is reconstructed.
•
Bit 3:0 — Drive # being replaced
0 = none
1h . . . Ah = drive 1h . . . Ah
•
Bit 7:4 — Reserved
Bank Status
Word reflecting the current active status of the bank. The bank-
mounted bits (bit 15:12) indicates whether the bank is MOUNTED.
The drive-mount bits (bits 9:0) indicate the mount status of each drive
since the last Bank Mount Sequence occurred. Normal host read/write
is permitted only if bit 15 is set (bank-mounted). If any one or more
drives required for a normal host read/write is write-protected, the
bank as a whole is protected from write Transfer commands. However,
formatting is still possible on any drives not write-protected at the
drive level.
•
Bit 9:0 — Drives mounted
0 = not mounted
1 = mounted (System Area correctly read)
•
Bit 11:10 — Reserved
•
Bit 15:12 — Bank mounted
15=0, 14=0, 13=0, 12=0 — Bank drive ID zero or invalid
15=0, 14=0, 13=0, 12=1 — Not enough mounted drives for
valid configuration
15=0, 14=0, 13=1, 12=0 — Too many drive flaws
15=1, 14=0, 13=0, 12=0 — Bank mounted (read/write)
15=1, 14=0, 13=0, 12=1 — Bank mounted (read only)
Count
Word specifying the bank size in number blocks. Maximum number of
blocks in bank.
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Configuration Data A–13
