
B–62073E–1/042. INTERFACE BETWEEN CNC AND PMC–NA OR NB
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(2) Specifying successive velocity commands
When the blocks of velocity command are successively specified, the system can execute them without
stopping at the end of each block. This can be executed only when the following conditions are satisfied:
1 While a block is being executed, the block of the next velocity command is buffered.
2 The velocity command skip signal is set high to terminate the current block.
Set the skip signal high.
The feed rate varies without halt.
Feed rate
N1 N2
Time
Fig. 2.3.81 (c)
Example When the following commands are specified, the PMC sequence becomes as illustrated be-
low:
M80 ; Executes the miscellaneous function that selects the velocity command.
S200 ; Specifies a rotation speed of 200 rpm.
⋅
⋅
S300 ; Specifies a rotation speed of 300 rpm.
S100 ; Specifies a rotation speed of 100 rpm.
⋅
⋅
M81 ; Cancels the velocity command.
PMC sequence
Velocity co0mmand
S200 S300 S100
SF
Command block
PMCAx
CNCAx
BUFx (Buffer)
Velocity command skip signal
Actual feed rate
S300
S200
Time
Fig. 2.3.81 (d) Sequence of changing feed rate without halt