Use this system macro to:
- Place output messages or link control blocks on CCP queues for
transmission on synchronous link lines.
- Restart (wake up) data transmissions by the output CCP after interruption
of data transmissions across a link.
- Note:
- The link control block (LCB) transmissions had not necessarily been
interrupted.
Format
Notes:
- symbol1
- symbol2
- symbol3
- label
- A symbolic name can be assigned to the macro statement
- symbol1
- This identifies the class of PLONC macro, which are:
MSG
LCB
WKP.
- symbol2
- If symbol1 is MSG, a core block reference word (D0-DF) must be specified
as parameter two. If symbol1 is LCB or WKP, the queue identity (LNK or
CHN) must be specified as parameter two.
- symbol3
- This is relevant only if symbol1 MSG and specifies that the message block
is to be added to the TOP or BTM (bottom) of the queue.
Entry Requirements
- If symbol1 is WKP, then the symbolic line number of the channel must be
right justified in R14.
- If symbol1 is LCB, then additionally R15 must contain the link control
block.
- If symbol1 is MSG, the message to be sent must be contained in a block of
core storage attached to the ECB at the specified level (symbol2).
Return Conditions
- Control is returned to the next sequential instruction (NSI).
- The contents of scratch registers (R14, R15) are unknown. The
contents of the remaining operational registers and the condition code are
saved during processing of this macro.
- If symbol1 is MSG, the specified core block reference word (CBRW) is
initialized to indicate that a block of storage is no longer held.
Programming Considerations
- This macro can only be run on the main I-stream.
- This macro must be used only by synchronous link control (SLC).
- The CAIEQ macro must also be called by the program issuing the PLONC macro
so that the assembler may be able to resolve the labels within the PLONC macro
expansion.
- The line number is checked to ensure that it is valid and within the legal
range for AI lines. If the line number is out of range, control is
transferred to the system error routines and the ECB is forced to exit.
- If symbol1 is MSG, a check is made by the control program (CP) to
determine if the ECB is holding a block of storage at the specified
level. If a block is not held, control is transferred to the system
error routines and the ECB is exited.
Examples
None.