FP MOVE EXPLAINED:

The FP Move is similar to the FL simple trapezoidal move, with one very important difference: it operates in Absolute mode. It is fully defined as "Feed to Position",

that will accelerate at a certain rate (AC) to a certain speed (VE) and continue until it nears the end of the move, and will slow at a certain rate (DE),

until it reaches the DI (Distance) value, which is the overall move length.

If you are unsure of the significance of "Absolute" mode, please read the "Intro to Motion Control" page. It is crucial to fully understand the concept

to properly utilize this particular move command.

Unlike the FL command, which has it's direction of rotation determined by whether the value is positive or negative, the FP command keeps track of a previous position

and will move forward or backward simply by comparing the commanded value to this previous value. If the commanded value is higher than the previous value ( position),

the drive will move forward. If the commanded value is lower than the previous value, the drive will move in the reverse direction.

The FP command is most frequently used in conjunction with 1 of 2 other commands, the SP (Set Position) and SH (Seek Home) commands. SP allows the user to

set the position of the drive at it's current location. SP0 would effectively establish a Home position that all other FP commands would be based on. SP could

also be any value within the range of the drive, such as -100,000 or 5000, effectively establishing an offset.

SH on the other hand, starts a homing process, so the drive will go thru a searching process to find a Home sensor. Ordinarily, on a linear table for example, there

would be End-Of-Travel switches, and a Home sensor. Once the drive is properly configured ( shown under the Homing and Absolute example ), then issuing the SH

command would start the motor turning, and it would turn until it encountered the Home sensor, or an Overtravel switch. If it's the Home sensor, the drive would record the

position and stop, then reverse if necessary to get back to the recorded position. If the drive encountered an EOT switch first , it would stop and reverse direction to find the

Home sensor.

If the FP5000 command was sent to the drive, it would go forward a certain distance. If FP1000 is then sent, this would cause the drive to reverse back 80%

of the original move.

Sent to dri

"Motor Disable", always do this when changing Command Mode settings.

"MD"

CM21

"Command Mode 21", makes sure the drive is set to Point-to-Point positioning mode.

"CM21"

"Accel", sets the accel, which will apply to the starting ramp. Both Accel and Decel are independently adjustable, if desired.

"AC2"

"Decel", sets the decel, which would apply to both changes decel ramps.

"DC2"

"Velocity", sets the peak velocity of the move.

"VE3"

"Electronic Gearing", this is the steps per rev setting of the drive. All examples use 10,000 steps per rev to simplify any math or calculations.

"EG1000"

"Motor Enable", enables the motor for motion

"ME"

"Distance", this is the overall move distance

"DI90000"

Saves parameters in drive.

"SA"

Initiates the move. Since this is an Absolute command, the drive would only make its' move one time (going to the position referenced by value DI).

"FP"

If we wanted the drive to move again, we could enter an FP command with a value different than the value in DI, such as FP7000, and then the

drive would go to that position. That doesn't change the value in DI, so if we issues a simple FP command, it would go back to position value DI.