Sfafus
and
Error
Bytes
At
the completion of each command the HDC will return status in the
last four bytes (1 2-1
5)
of the command block. The status format is
similar to that returned by the 'Request Sense'
SCSl command. This
four byte block contains error and status information pertaining to
the last block of data transferred or a non-disk operation executed
by the HDC. The ADV bit will be set, to indicate a valid address, if the
last operation required a disk access, otherwise ADV
=
0.
The logical unit number returned is simply the contents of the logical
unit field, where the error occurred, as defined in the drive control
block. For those commands that do not take a logical unit number as
an input parameter, the logical unit number returned in the com-
mand status byte
is
not meaningful.
A
list
of possible error codes, along with their descriptions, follows:
Error
Bytes
The logical sector address bytes are to be
in
the same format as that
defined in the command block.
Bits
3-0
of the error byte is used for
the error codes.
Bits
4,5
indicate the error type and
7
is the ADV bit.
Bit
6
is not used presently.
Disk Drive Error Codes (Type
0)
0
No error
1 No Index
2 Seek not complete
3
Write fault
4
Drive not ready
6
Track 0 not found
Controller Error Codes (Type 1)
11 Uncorrectable data error
12 Address mark not found
13 Sector not Found, Read
14 Sector not Found, Write
15
IDNF error
Command Error Codes (Type 2)
20 lnvalid command
21 Invalid sector address
22 Invalid
LUN
Hardware Error Codes (Type
3)
30
RAM failure (HDC)
31 ROM
Checksum Error
32 Host DMA status error
To Next Page
Loading...
