
B–62073E–1/042. INTERFACE BETWEEN CNC AND PMC–NA OR NB
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2.3.12 Function to compensate for manual intervention during automatic operation
The function to compensate for manual intervention during automatic operation can be used when specifying
an M code without buffering. The procedure is described below, using an example in which an M code without
buffering is specified with a move command.
(1) G00 G91 Z–50. Mxxx ; is specified (Mxxx being an M code without buffering).
(2) Code signals M0 to M31 are output, while at the same time, strobe signal MF goes high. Z–axis distribution
then begins.
(3) Upon detecting that signal MF has gone high, read the code signals at the PMC and perform the requested
operations, including manual intervention. To perform these operations after a move command, specified
in the same block, has been executed, wait until distribution end signal DEN or IPEN goes high. (The timing
chart shows a case where the operator waits for the distribution process to end.)
(4) Once the requested operations have been completed, select absolute switch signal ABS and set manual
intervention compensation request signal MIGET high.
When the codes for the spindle–speed function, tool function, second miscellaneous function, etc. are spe-
cified, wait for all these functions to be completed before attempting to set finish signal FIN high.
(5) After signal FIN has maintained its high state for a specified time, the control unit sets signal MF low to notify
the PMC that it has received signal FIN.
(6) Upon detecting that signal MF has gone low, set signal FIN low at the PMC. Do not change the state of
signals ABS or MIGET.
(7) Setting signal FIN low completes the sequence of the miscellaneous function. The control unit then pro-
ceeds with the compensation for manual intervention and, when completed, sets manual intervention com-
pensation finish signal MIFIN high.
(8) Upon detecting that signal MIFIN has gone high, set signal MIGET low to notify the control unit of the receipt
of signal MIFIN.
(9) Upon detecting that signal MIFIN has gone low, the control unit sets signal MIFIN low. This completes the
processing of the manual intervention compensation function.
(10)The control unit starts to read the next NC code.
The timing chart for the above procedure is shown below.
Example Timing chart for function to compensate for manual intervention during automatic operation
M code
Move command
Code signals
Strobe signal
Distribution end signal
PMC operations
ABS switch
Manual intervention
compensation request
signal
Finish signal
Manual intervention
compensation finish
signal
Reading the next block
Mxxx
M0-M31
MF
DEN, IPEN
ABS
MIGET
FIN
MIFIN
T-FIN
(1)(2) (3) (4) (5) (6) (7) (8)(9)(10)