ADLINK PCI-8258 - Manual (Page 185)

Motion Control Theory 171
PCI-8254 / PCI-8258
Structure of the VAO module
4.10.3.2 Control Modes
Your PCI-8254/8 VAO module now supports three control nodes:
a. Mode1: PWM mode
This control mode adjust PWM duty cycle according to fixed PWM
frequency and variable speeds as shown in figure below. The fixed
PWM frequency is 1/T and the PWM duty cycle W
1
/T, W
2
/T and
W
3
/T based on VAO table under speed V
1
, V
2
and V
3
with
different PWM pulse width at W
1
, W
2
and W
3
. See below for
details on VAO table. To use this control mode to set
1. Set up control mode: Use APS_set_vao_param ( ) to set
up value of VAO_TABLE_OUTPUT_TYPE parameter to 0x1 .
2. Set up fixed PWM output frequency:
Use APS_set_vao_param( ) to set up parameter
VAO_TABLE_PWM_Config in unit of Hz. Valid frequency
input range now is 3Hz ~ 50MHz.