PWM Operation in Wait Mode

12.8 PWM Operation in Wait Mode

When the microcontroller is put in low-power wait mode via the WAIT instruction, all clocks to the PWM module will continue to run. If an interrupt is issued from the PWM module (via a reload or a fault), the microcontroller will exit wait mode.

Clearing the PWMEN bit before entering wait mode will reduce power consumption in wait mode because the counter, prescaler divider, and LDFQ divider will no longer be clocked. In addition, power will be reduced because the PWMs will no longer toggle.

12.9 Control Logic Block

This subsection provides a description of the control logic block.

12.9.1 PWM Counter Registers

The PWM counter registers (PCNTH and PCNTL) display the 12-bit up/down or up-only counter. When the high byte of the counter is read, the lower byte is latched. PCNTL will hold this latched value until it is read. See Figure 12-33and Figure 12-34.

Address:

Read:

Write:

Reset:

$0026
Bit 7	6	5	4	3	2	1	Bit 0

0	0	0	0	Bit 11	Bit 10	Bit 9	Bit 8


0	0	0	0	0	0	0	0
	= Unimplemented
	= Unimplemented

Figure 12-33. PWM Counter Register High (PCNTH)

Address:

Read:

Write:

Reset:

$0027
Bit 7	6	5	4	3	2	1	Bit 0

Bit 7	Bit 6	Bit 5	Bit 4	Bit 3	Bit 2	Bit 1	Bit 0


0	0	0	0	0	0	0	0
	= Unimplemented
	= Unimplemented

Figure 12-34. PWM Counter Register Low (PCNTL)

MC68HC908MR32 • MC68HC908MR16 Data Sheet, Rev. 6.1

Freescale Semiconductor

143

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.

Freescale Semiconductor MC68HC908MR16 manual PWM Operation in Wait Mode, Control Logic Block

Models: MC68HC908MR16 MC68HC908MR32