
B–62073E–1/04 2. INTERFACE BETWEEN CNC AND PMC–NA OR NB
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(b) Automatic operation stop signal (SP)
[Classification]
Input signal
[Function] This signal stops automatic operation, or locks the start of automatic operation. It stops
execution of manual numerical commands, or locks the start of manual numerical command
execution.
[Operation] When the signal goes low, the control unit functions as described below.
1 If the control unit is performing automatic operation, it stops it. Once automatic operation
is stopped, it is not resumed even if
SP goes high again. To resume automatic opera-
tion, automatic operation start signal ST must go low from the high status.
2 If the control unit is executing manual numerical commands, it stops the execution. Once
the command execution is stopped, it cannot be continued.
3 In other than the above cases, the control unit does not perform any special operation.
While
SP is low, automatic operation start signal ST is locked.
NOTE If SP goes low during automatic operation, it is stopped immediately. In the following cases,
however, automatic operation continues until it reaches a point at which it can be stopped. At
that point operation is stopped. (Operation is stopped at this point even if
SP goes high again
before this point is reached.)
1 Cutting feed is in progress in the tapping canned cycle. In this case, operation is stopped
when return to the reference position or initial position has been performed after the ter-
mination of tapping.
2 Threading is in progress. In this case, operation is stopped when a non–threading block
subsequent to the blocks of the current threading operation has been executed. If
SP
is still low, however, operation is stopped immediately after that non–threading block
starts (at the start point of the block).
3 A control variable that disables feed hold is set in a custom macro. In this case, operation
is stopped when a subsequent block that clears the control variable for the first time has
been executed. If
SP is still low, however, operation is stopped immediately after that
block starts (at the start point of the block).
(c) Single block signal (SBK)
[Classification]
Input signal
[Function] This signal selects single–block operation.
[Operation] If the signal goes high, the control unit functions as described below.
1 If the control unit is performing automatic operation, it stops operation after the executing
block terminates. To execute the next block, automatic operation must be started again.
2 Unless the control unit is performing automatic operation, the control unit does not per-
form any particular operation. When automatic operation is started while SBK is left high,
operation stops after one block is executed. This function is useful for executing a pro-
gram block by block.
NOTE 1 The high or low state of SBK is determined at the end point of a block being executed. When
SBK is low at the end of a block, single–block operation cannot result even if SBK goes high
at the start of a block or during block execution.
NOTE 2 If SBK is high at the end of a block, operation is stopped immediately. In the following cases,
however, operation continues until it reaches a point at which it can be stopped. At that point
operation is stopped. (If SBK goes low before this point is reached, operation does not stop.)
1 A cycle operation, such as a canned cycle, is in progress. In this case, which block, among
the blocks performing cycle operation, accepts single block operation depends on the
cycle. Refer to the description of cycles in the programming description.
2 A control variable that disables single block operation is set in a custom macro. In this
case, when a block that clears that control variable appears, single block operation is
accepted and operation is stopped if SBK is still high.
NOTE 3 SBK is invalid for manual numerical commands. Manual numerical commands can be
specified for one block only, so single block operation is unnecessary.