Reference Manual

Turbo PMAC/PMAC2 Software Reference
Turbo PMAC Global I-Variables 176
Isx11 Coordinate System ‘x’ User Countdown Timer 1
Range: -8,388,608 - 8,388,607
Units: servo cycles
Default: 0
Isx11 provides an automatic countdown timer for user convenience. If Coordinate System ‘x’ is activated
by I68, Isx11 will count down one unit per servo cycle. The user may write to this variable at any time,
and it will count down from that value. Typically user software will then wait until the variable is less
than another value, usually zero. The software accessing Isx11 does not have to be associated with
Coordinate System ‘x’.
Isx11 is a signed 24-bit variable, providing a range of -2
23
(-8,388,608) to +2
23
-1 (8,388,607). If active, it
counts down continually until it reaches its maximum negative value of -8,388,608. It will not roll over.
Most people will just use the positive range, writing a number representing the number of servo cycles for
the period to the variable, then waiting for it to count down past 0.
If Isx14 is set to a non-zero value when the MOVETIME command is issued to this coordinate system,
Isx11 will automatically be written to with a value of the number of servo cycles equal to the time left in
the commanded move minus Isx14 milliseconds. This lets the user easily monitor Isx11 to find out when
the move is Isx14 milliseconds from the end.
The following code shows how Isx11 could be used in a PLC to turn on an output for a fixed period of
time.
M1=1 ; Set the output
I5111=2259 ; Set the timer to 1 second (2259 servo cycles)
WHILE (I5111>0) ; Wait for timer to count down
ENDWHILE
M1=0 ; Clear the output
Isx12 Coordinate System x User Countdown Timer 2
Range: -8,388,608 - 8,388,607
Units: servo cycles
Default: 0
Isx12 provides an automatic countdown timer for user convenience. If Coordinate System x is activated
by I68, Isx12 will count down one unit per servo cycle. The user may write to this variable at any time,
and it will count down from that value. Typically, user software will then wait until the variable is less
than another value, usually zero. The software accessing Isx12 does not have to be associated with
Coordinate System x.
Isx12 is a signed 24-bit variable, providing a range of -2
23
(-8,388,608) to +2
23
-1 (8,388,607). If active, it
counts down continually until it reaches its maximum negative value of -8,388,608. It will not roll over.
Most will just use the positive range, writing a number representing the number of servo cycles for the
period to the variable, then waiting for it to count down past 0.
The following code shows how Isx12 could be used in a PLC to turn on an output for a fixed period of time.
M1=1 ; Set the output
I5112=2259 ; Set the timer to 1 second (2259 servo cycles)
WHILE (I5112>0) ; Wait for timer to count down
ENDWHILE
M1=0 ; Clear the output