Several operands on the PCCU definition statement are used to define channel characteristics. If you do not define a channel in a channel-attachment major node, the values on the PCCU definition statement are used because the channel is implicitly defined and activated automatically when the NCP is activated.
However, when you define the channel in a channel-attachment major node, the definition statements in the channel-attachment major node contains operands similar to those on the PCCU definition statements.
For a data host, the CHANCON, MAXDATA, and DELAY operands on the PCCU definition statement are replaced by the same operands on the PU definition statement in the channel-attachment major node. In addition, the CUADDR operand on the PCCU definition statement is replaced by the ADDRESS operand on the LINE definition statement in the channel-attachment major node.
Activating the channel-attachment major node to activate the channel causes VTAM® to use the values defined in the channel-attachment major node. Later, if the NCP is activated, these same operands, if they appear on the NCP’s PCCU definition statements, are ignored. If you define the channel in a channel-attachment major node and would like to avoid confusion concerning these operands, avoid coding duplicate values on the PCCU definition statement.
The RNAME operand on the PCCU definition statement can name a link station associated with a channel link defined in a channel-attachment major node. When the host activates each NCP, the link station and link defined in the channel-attachment major node representing the channel are activated automatically.