Commodore 1581 - CMD 2: Write; CMD 5: Inquire Disk

OUTPUT: One burst status byte, followed by burst data, is sent for each sector trans-
fered. An error prevents data from being sent unless the E bit is set.
CMD 2—WRITE
BYTE
00
01
02
03
04
05
06
BIT 7
0
0
L
6
1
0
E
5 4 3
0 1 0
1 1 0
X S 0
DESTINATION TRACK
DESTINATION SECTOR
NUMBER OF SECTORS
NEXT TRACK (OPTIONAL)
2
1
0
0
1
0
0
1
0
1
0
N
RANGE: All values are determined by the particular disk format and format of transla
tion table.
SWITCHES: L—logical flag (1 = do logical to physical translation)
E—ignore error (1 = ignore)
S—side select
N—drive number
PROTOCOL: Burst data to the drive, then host must perform the following: fast serial
input, pull the clock low and wait for the burst status byte, pull clock
high, go output for multi-sector transfers and continue.
CONVENTIONS: Before you can READ or WRITE to a diskette, it must be logged-in
using either the INQUIRE DISK or QUERY DISK FORMAT command
(both are described later). This must be done once each time you
change diskettes.
INPUT: Host must transfer burst data.
OUTPUT: One burst status byte following each WRITE operation.
CMD 5—INQUIRE DISK
BYTE
00
01
02
BIT 7
0
0
X
6
1
0
X
5
0
1
X
4
1
1
S
3
0
0
0
2
1
0
1
1
0
0
0
0
1
0
N
SWITCHES: N—drive number
PROTOCOL: Burst handshake
OUTPUT: One burst status byte following each INQUIRE DISK operation.
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