Configuring a High-speed Output (PWM)

You can use certain outputs as High-speed Outputs (HSO) via PWM (Pulse Width Modulation). When you select a High Speed Output in the Hardware, the Select Operand and Address dialog box appears three successive times, allowing you to link operands for the following values:

• Duty Cycle

  The ratio of the "on" period of a cycle to the total cycle period. This value may be from 0-1000, and is expressed as a percentage.

  If, for example, the constant 750 is stored into the Duty Cycle operand, the duty cycle is equal to 75.0% This means that the pulse will hold a positive state during 75.0% of the total cycle.

• Frequency (F)

  Note that F=1/T, where T is the duration time of a complete cycle.  

  The following table shows the available frequency settings. Refer to product specifications for the maximum frequency specific to your controller model.

  Controller Model	Frequency Range	Software Units
  Enhanced Vision, V5xx/V1xxx	0.1Hz to 100kHz	0.1Hz (500Hz  = 5,000)
  Standard Vision, V2xx/V530	8Hz to 50kHz	1Hz (500Hz=500)
  Enhanced Vision, V130/V350/V430 Samba SM35/SM43	5Hz to 200kHz	1Hz (500Hz=500)
  Standard Vision, V120	3Hz to 10kHz	1Hz (500Hz=500)

• Run

  Changes the operating mode of the output from normal output mode to HSO mode:

  0 (SET)=Normal Mode, 1 (RESET): HSO Mode.

In the figure below, MI 22 Duty Cycle Value is equal to 250. This results in the duty cycle being 25% of the total cycle time.

Configuring the HSO