Measurement Computing CIO-CTR05 Counter PWM

CIO-CTR05 Counter PWM block (not recommended)


Simulink® Real-Time™ Library of Drivers No Longer Recommended for Use


The CIO-CTR05 has one AM9513A chip with five counters.

The CIO-CTR05 PWM driver programs the AM9513A for PWM (Pulse Width Modulation) signal generation (a square wave with fixed frequency and variable duty cycle). The block has one input which defines the variable duty cycle between 0 and 1. For the corresponding counter channel, the PWM signal is output at the pin named OUT.

Scaling Input to Output

I/O Module Output

Block Input Data Type




0 to 1

Block Parameters


From the list, choose 1, 2, 3, 4, or 5 to select which counter is used with this driver block. One block is required for each counter used.

Frequency base

From the list, choose F1=5MHz, F2=500kHz, F3=50kHz, F4=5kHz, or F5=500Hz to set the base frequency. The XTAL frequency is assumed to be 1 MHz, therefore the jumper on the CIO-CTR05 has to be in position 1 MHz not 5 MHz.

Relative output frequency

Enter a value between 0 and 0.25. The Relative output frequency is multiplied by the Frequency base to set the fixed output frequency of the PWM-signal.

For example, if the output frequency of a square wave has to be 17.5 kHz, then choose F2=100kHz as the Frequency base and enter 0.175 as the Relative output frequency. 100 kHz x 0.175 = 17.5 kHz

Level sequence of square wave

From the list, choose either high-low or low-high:

  • If you choose high-low, the square wave period starts with the TTL high part followed by the TTL low part.

  • If you choose low-high, the square wave period starts with the TTL low part followed by the TTL high part.

In either case, the duty cycle entering the block defines the duration of the TTL high part.

Level when disarmed

From the list, choose either high or low. The counter is automatically disarmed when the real-time application is not running and gets armed when the application begins running. This parameter sets the TTL level when the counter is disarmed.

Sample time

Enter the base sample time or a multiple of the base sample time. The sample time indicates the update rate of registration on the input (Duty Cycle)

Base address

Enter the base address of the board. This entry must correspond to the DIP switch setting on the board. For example, if the DIP switch setting is 300 (hexadecimal), enter 0x300.

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