Interactive Command Completion - HP 30242 Installation And Service Manual

Lan/3000 link local area network interface controller
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Principles of Operation
INTERACTIVE COMMAND COMPLETION. This response is given when the LANIC completes the
execution of an interactive command. The command -specific bits of the response code contain status and
error codes whose meanings depend on the associated command as shown below.
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
0
0
0
Completion status
Command code
I
I
I
I
I
I
I
I
I
I
I
Command code
Completion status
=
Command code originally given
=
See below and paragraph "Self-test"
00 - command executed correctly
01
sync between driver and LANIC established
(e.g., an all-ones word written into CR)
02 - illegal length command
03 - command not found
04 - command doesn't match length
08 - host buffer crosses bank boundary
09 - non-word address on download or dump
OA - checksum didn't check (DOWNLOAD command)
OB - illegal start address (START CODE command)
INTERACTIVE COMMAND ACKNOWLEDGEMENT. This response is given after the firmware reads
the first word of a multiple-word command from the CR. This response is useful for avoiding the host
software busy-wait on CRFULL after the first word of a multiple-word command has been written to
the DR. This problem is due to the fact that the first word may not be accepted by the LANIC for
several milliseconds, but the succeeding words are handshaken with negligible delay. A command
acknowledgement response is not given for a single-word command as it is followed by a command
completion response anyway. See below.
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
0
0
1
Undefined
I
I
I
I
I
I
I
I
I
I
I
I
Feb 8S
3-7

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