Reference Manual

Turbo PMAC/PMAC2 Software Reference

Turbo PMAC Program Command Specification 463

PVT{data}

Function: Set Position-Velocity-Time mode

Type: Motion program (PROG and ROT)

Syntax: PVT{data}

where:

 {data} is a positive constant or expression representing the time of a segment in milliseconds

This command puts the motion program into Position-Velocity-Time move mode, and specifies the time

for each segment of the move, in milliseconds. In this mode, each move segment in the program must

specify the ending position and velocity for the axis. Taking the starting position and velocity (from the

previous segment), the ending position and velocity, and the segment time, Turbo PMAC computes the

unique cubic position profile (parabolic velocity profile) to meet these constraints.

If global I-variable I42 is set to the default value of 0, the specified time uses the move time register, and

has a range of 0 to 4095.9998 milliseconds, with a resolution of ¼-microsecond. In this case, if the

segment time in a sequence of moves is changed on the fly, either another PVT command is used, or a TM

command.

If I42 is set to 1, the specified time uses the acceleration time register, and has a range of 0 to 8,388,607

milliseconds(about 2 hours, 20 minutes), with a resolution of 1 millisecond. In this case, if the segment

time in a sequence of moves is changed on the fly, either another PVT command is used, or a TA

command.

The segment time in a sequence of moves can be changed on the fly, either with another PVT command,

or with a TM command. TS, TA, and F settings are irrelevant in this mode.

The PVT command takes the program out of any of the other move modes (LINEAR, CIRCLE, SPLINE,

RAPID), and any of the other move mode commands takes the program out of PVT move mode.

Refer to the Writing and Executing Motion Programs section of this manual for more details of this mode.

Examples:

INC ; incremental mode, specify moves by distance

PVT200 ; enter this mode -- move time 200ms

X100:1500 ; cover 100 units ending at 1500 units/sec

X500:3000 ; cover 500 units ending at 3000 units/sec

X500:1500 ; cover 500 units ending at 1500 units/sec

X100:0 ; cover 100 units ending at 0 units/sec

PVT(P37)