
B–62073E–1/04 2. INTERFACE BETWEEN CNC AND PMC–NA OR NB
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(a) Command spindle speed signals (RO0 to RO15 [#1, #2])
[Classification]
Output signals
[Function] These signals report a specified spindle speed. If constant surface speed control is exer-
cised, the spindle speed reported by the signal is one specified after such control is exercised.
These signals consist of 16 binary signals. A spindle speed is related to these signals as fol-
lows:
Spindle speed
+
ȍ
15
i+0
(2
i
Vi) ń 10
N
RPM
whereVi = 0 when ROi is low
Vi = 1 when ROi is high
N represents a number (0 to 3) set by a parameter.
The parameter N is commonly applied to the other output signals (actual spindle speed, maxi-
mum spindle speed) as well as this signal.
[Output Condition]
These signals are output at all times. These signals change only during constant surface sig-
nal control, or when S is specified in a command program. During constant surface signal
control, these values usually change every 16 msec.
(b) Maximum spindle speed signals (MR0 to MR15 [#1, #2])
[Classification]
Output signals
[Function] These signals report a maximum spindle speed specified by G92Sxxx. Whether to clamp the
spindle signal to this maximum spindle speed only during constant surface speed control or
at all times depends on the PMC specifications. These signals consist of 16 binary signals.
A spindle speed is related to these signals as follows:
Spindle speed
+
ȍ
15
i+0
(2
i
Vi) ń 10
N
RPM
whereVi = 0 when MRi is low
Vi = 1 when MRi is high
N represents a number (0 to 3) set by a parameter.
The parameter N is commonly applied to the other output signals (command spindle speed,
actual spindle speed) as well as this signal.
[Output Condition]
These signals are output at all times. These signals change only when G92Sxxx is specified
in a command program.
(c) Actual spindle speed signals (AR0 to AR15 [#1, #2])
[Classification]
Output signals
[Function] These signals report the actual spindle speed calculated using a feedback pulse signal from
a position coder mounted on the spindle.
These signals consist of 16 binary signals. A spindle speed is related to these signals as fol-
lows:
Spindle speed
+
ȍ
15
i+0
(2
i
Vi) ń 10
N
RPM
whereVi = 0 when ARi is low
Vi = 1 when ARi is high
N represents a number (0 to 3) set by a parameter.
The parameter N is commonly applied to the other output signals (command spindle speed,
maximum spindle speed) as well as this signal.
[Output Condition]
These signals are output at all times. These signals usually change every 64 msec.
NOTE An absolute error of about 0.5 rpm may be observed as a measuring error.