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Remote Command Control
Message Set
Chapter 10
106
RC Control Header Fields
Figure 10.1 shows the format of the RC control message packet including
the RC header fields. The RC control header fields are those header fields
common to all RC control message set transmissions. Here we describe
these RC control header fields:
TNS
2 Bytes
USER
NODE
LINK
STS
STS (RC Control Message Status) — In a command packet, this
one-byte field has a hexadecimal value of 00. In a reply packet, this
one-byte field indicates the status of RC control message transaction.
This status field does not indicate the status of the remote command
transaction initiated at the remote node. This field indicates either a
successful transaction completion or an error as follows:
STS Code
(Hex)
Description
STS Code
(Hex)
Description
00
Transaction successfully completed.
C9
Invalid NODE number in the remote command.
C0
Invalid CMDfield value in the RC message.
CA
Invalid USER number in the remote command.
C1
Protect violation; access not allowed.
CB
Invalid SBQ number (Must Be = 1).
C2
Remote command not found.
CC
Invalid DBQ number (Must Be = 1).
C3
RC Control command invalid in this host mode.
CD
Invalid source memory address.
C4
Unable to determine remote processor mode.
CE
Invalid destination memory address.
C5
Failure to store or delete a remote command in
nonvolatile memory.
CF
Value in RC control message SIZE field does not match
the size of the remote command.
C6
Invalid SEL code.
D0
Value in RCQ field in
initiate
RC message does not
match the quantity of remote commands identified.
C7
Invalid CMDfield value in the remote command.
D1
Can't store/initiate/delete; no remote command space
available; 256 remote commands stored.
C8
Invalid LINK number in the remote command.
TNS (Transaction) — This two-byte field indicates which RC control
message transaction is taking place. A complete transaction consists of
the command packet and the corresponding reply packet. When the host
computer initiates a transaction, it must increment the TNS value to
distinguish the packets of the current transaction from the packets of the
previous transaction. When another station receives an RC control
command packet from your host computer, it must copy the TNS value
into the TNS field of the corresponding reply packet. This helps the