
B–61863E/15
2. SEQUENCE PROGRAMPMC SEQUENCE PROGRAM
51
Input signals (M function, T function, etc.) from the CNC and those (cycle
start, feed hold, etc.) from the machine tool are sent to the PMC.
Signals for the CNC (cycle start, feed hold, etc.) and those for the machine
tool (tunret rotation, spindle stop, etc.) are output from the PMC.
Fig. 2.4 shows the relationship between these signals and the PMC.
Input signals are entered in the input memory of PMC and output signals
are issued from PMC.
As shown in Fig. 2.5, the input signals are synchronized only in the 2nd
level sequence part.
Input signals from
CNC
Input memory of CNC
1st level
sequence part
Sequence program
2nd level
sequence part
PMC
3rd level
sequence part
Input signals from
CNC
Input signals from
machine tool
2nd level synchronous
input signal memory
Output signals to the
machine
Input signals from
machine
Input signal memory
Output signalmemory
Output signals to
machine tool
Input signals from
machine tool
CNC
Output signals to
CNC
MT
Transmitted
every 2 ms
Transmitted every 8 ms
Transmitted at the
start of 2nd level
Output memory of CNC
Fig. 2.5 PMC I/O signals
2.5
PROCESSING I/O
SIGNALS