BASIC commands
PROGRAMMING MANUAL
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3.2.224 P_GAIN
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3.2.225 PI
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3.2.226 PMOVE
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3.2.227 POS_OFFSET
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Type
Axis parameter
Syntax
P_GAIN
Description
The
P_GAIN
parameter contains the proportional gain. The proportional out-
put contribution is calculated by multiplying the Following Error with the
P_GAIN
parameter value. The default value of
P_GAIN
for MECHATRO-
LINK-II Speed axis (
ATYPE = 41
) is 131072. The default value for Flexible
axis Servo (
ATYPE = 44
) is 1.0.
The proportional gain sets the stiffness of the servo response. Values that are
too high will cause oscillation. Values that are too low will cause large Follow-
ing Errors.
Note: In order to avoid any instability the servo gains should be changed only
when the
SERVO
is off.
Arguments
N/A
Example
No example.
See also
D_GAIN
,
I_GAIN
,
OV_GAIN
,
VFF_GAIN
.
Type
Constant (read-only)
Syntax
PI
Description
The
PI
constant returns the numerical constant value of approximately
3.14159.
Arguments
N/A
Example
circum = 100
PRINT "Radius = "; circum/(2*PI)
See also
N/A
Type
Task parameter (read-only)
Syntax
PMOVE
Description
The
PMOVE
parameter contains the status of the task buffers. The parameter
returns
TRUE
if the task buffers are occupied, and
FALSE
if they are empty.
When the task executes a movement command, the task loads the movement
information into the task move buffers. The buffers can hold one movement
instruction for any group of axes.
PMOVE
will be set to
TRUE
when loading of
the buffers has been completed. When the next servo interrupt occurs, the
motion generator loads the movement into the next move (
NTYPE
) buffer of
the required axes if they are available. When this second transfer has been
completed,
PMOVE
is cleared to 0 until another move is executed in the task.
Each task has its own
PMOVE
parameter. Use the
PROC
modifier to access
the parameter for a certain task. Without
PROC
the current task will be
assumed.
Arguments
N/A
Example
No example.
See also
NTYPE
,
PROC
.
Type
System parameter
Syntax
POS_OFFSET=value
Description
For Piezo Operation. This keyword allows a positive offset to be applied to the
output
DAC
signal from the servo loop. The offset is applied after the
DAC_SCALE
function. An offset of 327 will represent an offset of 0.1 volts for
axis with servo output generated by a 16 bit DAC. It is suggested that as off-
set of 65% to 70% of the value required to make the stage move in an open
loop situation is used.
Arguments
N/A
Example
No example.
