This text shows how to configurate the PWM output using

QFIRE Studio

.

Introduction

In

QFIRE Studio

, it is possible to use the PWM block as an output block. This block receives its duty cycle by the input. Figure 1 shows the PWM block.

In Figure 1, there are two blocks. Theses blocks represent two different output port. The upper block is the high channel and the lower block is the low channel. But, there is a "0" in the block because these ports belong to the same module.The configuration of these parameters are made by the PWM Output Properties.

Figure 2 shows the Module, High and Low configuration. Furthermore, it is possible to open the PWM Configuration. Other way to open the PWM Configuration is using the PWM Configuration Icon located in the Icon Bar.

In Figure 4, it is possible to see that

QFIRE CTR-101

has four diferente modules. Each one of them can be configurate in a diferente way. The parameters are:

• Enable Module.
• Frequency configuration.
• Generation Mode.
• Alignment Mode.

Frequency configuration.

When a PWM module is enabled, it is possible to access the other parameters. The first of them is the Frequency configuration. This parameters set the frequency of the PWM cycles. Figure 5 shows all possible frequencies available.

It is important to understand that the duty cycle value only is updated in the end of the PWM cycle. It is necessary to take care because some tasks can be faster than the PWM frequency.

Generation Mode

The next parameter is the Generation Mode. As can be see in Figure 6, it is possible to choose between Independent and Complementary mode. Their behavior is exemplified in Figure 7.

As can be seen, when the Generation Mode is Independent, the Low Output channel can have a different duty cycle. But, when the Generation Mode is Complementary, the Low Output channel has the complementary duty cycle, i.e., if the High Output channel has a duty cycle of 80%, the Low Output will have a 20% of duty cycle.

Alignment Mode

There is two alignment mode available in

QFIRE CTR-101

, edge and center. The behavior of them is showed by the Figure 8

When the alignment is set to Edge, the PWM duty cycle stars in the begging of the cycle and when the alignment is set to Center, the duty cycle is centralized in the cycle as can be see in Figure 8.