Visara LINCS Central Control - Manual (Page 172)

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LINCS Central Control
707024-002
buffers condition, this command will be issued to the CHC to indicate that buffers are now
available for that address. If the host has been notified of the no buffers available condition,
the CHC will be notified when buffers become available via the Present Asynchronous Status
CC Command when the asynchronous x‘44’, mentioned above, is presented.
Following a no buffers for all addresses condition, when buffers become available for all
addresses, this CC command will be issued to the CHC.
A Command Complete CHC message should be received from the CHC in response to this
CC command.
The format of the description and extended data is:
• Change Buffer Status Addr = xx Flags = xx
Present Asynchronous Status and Present Ending Status
These CC commands are issued to the CHC to request that status be presented on the channel.
When channel command processing is active and the status to be presented is associated with
a channel command, a Present Ending Status CC Command will be issued to the CHC. When
no channel command is active, command chaining is not active, and a Sense command is not
pending, if there is any asynchronous status to be presented on the channel, a Present
Asynchronous Status CC Command will be issued to the CHC.
Following acceptance of the status on the channel, the CHC will acknowledge that the status
has been presented by returning a Status Accepted CHC message to the CHC.
If, when requesting that asynchronous status be presented on the channel, the status cannot be
presented, the CHC will notify the CHP of this condition by returning a Command Not
Accepted CHC message.
The format of the description and extended data is:
• Present Async Status Addr = xx Flags = xx Status = xx
• Present Ending Status Addr = xx Flags = xx Status = xx
Go Online and Go Offline
These commands are issued to the CHC to request that the LINCS node be placed online to
the channel or taken offline from the channel.
When no channel command is active, command chaining is not active, and a sense command
is not pending, a Go Offline request can be made.
A Command Complete CHC message should be received from the CHC in response to both
CC commands. If the CHC is unable to Go Offline for any reason, a Command Not Accepted
CHC message should be received in response to the Go Offline CC command.
The format of the description and extended data is:
• Go Online
• Go Offline
Set Configuration Parameters
This command is issued to the CHC immediately following IML to notify the CHC of any
configuration parameters which affect LINCS operation on the channel. Information included
in this command includes Upper and Lower channel address, Data Transfer mode, Command
Retry Support, and Protocol.