Output Control

12.5.5 PWM Output Port Control

Conditions may arise in which the PWM pins need to be individually controlled. This is made possible by the PWM output control register (PWMOUT) shown in Figure 12-22.

Address:

Read:

Write:

Reset:

$0025

 

 

 

 

 

 

 

Bit 7

6

5

4

3

2

1

Bit 0

 

 

 

 

 

 

 

 

0

OUTCTL

OUT6

OUT5

OUT4

OUT3

OUT2

OUT1

 

 

 

 

 

 

 

 

 

 

0

0

0

0

0

0

0

0

 

= Unimplemented

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Figure 12-22. PWM Output Control Register (PWMOUT)

If the OUTCTL bit is set, the PWM pins can be controlled by the OUTx bits. These bits behave according to Table 12-6.

Table 12-6. OUTx Bits

OUTx Bit

 

Complementary Mode

 

Independent Mode

 

 

 

 

 

OUT1

1

— PWM1 is active.

1

— PWM1 is active.

0

— PWM1 is inactive.

0

— PWM1 is inactive.

 

 

 

 

 

 

OUT2

1

— PWM2 is complement of PWM 1.

1

— PWM2 is active.

0

— PWM2 is inactive.

0

— PWM2 is inactive.

 

 

 

 

 

 

OUT3

1

— PWM3 is active.

1

— PWM3 is active.

0

— PWM3 is inactive.

0

— PWM3 is inactive.

 

 

 

 

 

 

OUT4

1

— PWM4 is complement of PWM 3.

1

— PWM4 is active.

0

— PWM4 is inactive.

0

— PWM4 is inactive.

 

 

 

 

 

 

OUT5

1

— PWM5 is active.

1

— PWM5 is active.

0

— PWM5 is inactive.

0

— PWM5 is inactive.

 

 

 

 

 

 

OUT6

1

— PWM 6 is complement of PWM 5.

1

— PWM6 is active.

0

— PWM6 is inactive.

0

— PWM6 is inactive.

 

 

 

 

 

 

When OUTCTL is set, the polarity options TOPPOL and BOTPOL will still affect the outputs. In addition, if complementary operation is in use, the PWM pairs will not be allowed to be active simultaneously, and dead-time will still not be violated. When OUTCTL is set and complementary operation is in use, the odd OUTx bits are inputs to the dead-time generators as shown in Figure 12-15. Dead-time is inserted whenever the odd OUTx bit toggles as shown in Figure 12-23. Although dead-time is not inserted when the even OUTx bits change, there will be no dead-time violation as shown in Figure 12-24.

Setting the OUTCTL bit does not disable the PWM generator and current sensing circuitry. They continue to run, but are no longer controlling the output pins. In addition, OUTCTL will control the PWM pins even when PWMEN = 0. When OUTCTL is cleared, the outputs of the PWM generator become the inputs to the dead-time and output circuitry at the beginning of the next PWM cycle.

NOTE

To avoid an unexpected dead-time occurrence, it is recommended that the OUTx bits be cleared prior to entering and prior to exiting individual PWM output control mode.

MC68HC908MR32 • MC68HC908MR16 Data Sheet, Rev. 6.1

Freescale Semiconductor

135

Page 134 Page 136
Page 135
Image 135
Freescale Semiconductor MC68HC908MR16 PWM Output Port Control, OUTx Bits, OUTx Bit Complementary Mode Independent Mode
Page 134 Page 136

MC68HC908MR16, MC68HC908MR32 specifications

Freescale Semiconductor's MC68HC908MR32 and MC68HC908MR16 microcontrollers are part of the popular HC08 family, designed primarily for embedded applications. These microcontrollers are particularly favored in automotive, industrial, and consumer product sectors due to their reliability and versatility.

One of the standout features of the MC68HC908MR series is its CMOS technology, which enhances performance while minimizing power consumption. This makes these microcontrollers suitable for battery-operated devices. They operate at a maximum clock frequency of 2 MHz and offer a 16-bit architecture, providing a solid balance between processing power and efficiency.

The MC68HC908MR32 variant is equipped with 32KB of flash memory, which allows for the storage of complex programs and extensive data handling. In contrast, the MC68HC908MR16 features 16KB of flash memory, making it ideal for simpler applications. Both microcontrollers also come with 1KB of RAM, enabling efficient data processing and real-time operations.

Another significant characteristic of these microcontrollers is their integrated peripherals. They come with multiple input/output (I/O) pins, which allow for connectivity with various sensors and actuators. The built-in timer systems offer precise timing control for automotive and industrial applications, while the Analog-to-Digital Converter (ADC) provides essential conversion capabilities for various analog signals.

For communication purposes, the MC68HC908MR series includes a serial communication interface, enabling easy integration with other devices and systems. This versatility facilitates the development of complex systems that require interaction with external components.

Security is another crucial aspect of these microcontrollers. They have built-in fail-safe mechanisms to ensure reliable operation under various conditions, making them suitable for critical systems. Additionally, their robust architecture helps to safeguard against potential disruptions or attacks.

In summary, Freescale Semiconductor's MC68HC908MR32 and MC68HC908MR16 microcontrollers are key players in the embedded systems landscape. Their blend of power efficiency, integrated features, and scalability ensures they remain relevant for a wide array of applications, making them a favored choice among engineers and developers looking for dependable solutions in a competitive market.
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