actually, you can control the following using plsr:
1. frequency
2. number of pulses
3. ramp up time
when you wish to give a pulse more than 20000, then your command should be like this :
ex.
======================================
LD X0
PLSR K500 D0 D1 Y0
======================================
OR USING DPLSR :
======================================
LD X1
DPLSR K20000 K50000 D6 Y1
======================================
regarding of the ramp value, i think you cannot change the ramp up time from ramp down time. because they have the same reference (S3). and there is no completion flag for the PLSR halfway. completion flag (M8029) is on when pulse ramp completed its execution from ramp up to ramp down.
but first, before executing this command, be sure that your FX1n PLC is transistorized type.
hope it can help.