System Integration Module (SIM)

SBSW can be read within the break state SWI routine. The user can modify the return address on the stack by subtracting one from it.

14.7.2 SIM Reset Status Register

The SIM reset status register (SRSR) contains six flags that show the source of the last reset. Clear the SIM reset status register by reading it. A power-on reset sets the POR bit and clears all other bits in the register.

Address:

$FE01

 

 

 

 

 

 

 

 

BIt 7

6

5

4

3

2

1

Bit 0

 

 

 

 

 

 

 

 

 

Read:

POR

PIN

COP

ILOP

ILAD

MENRST

LVI

0

 

 

 

 

 

 

 

 

 

Write:

R

R

R

R

R

R

R

R

 

 

 

 

 

 

 

 

 

Reset:

1

0

0

0

0

0

0

0

R

= Reserved

Figure 14-15. SIM Reset Status Register (SRSR)

POR — Power-On Reset Bit

1 = Last reset caused by POR circuit

0 = Read of SRSR

PIN — External Reset Bit

1 = Last reset caused by external reset pin (RST) 0 = POR or read of SRSR

COP — Computer Operating Properly Reset Bit 1 = Last reset caused by COP counter

0 = POR or read of SRSR

ILOP — Illegal Opcode Reset Bit

1 = Last reset caused by an illegal opcode

0 = POR or read of SRSR

ILAD — Illegal Address Reset Bit (opcode fetches only)

1 = Last reset caused by an opcode fetch from an illegal address 0 = POR or read of SRSR

MENRST — Forced Monitor Mode Entry Reset Bit 1 = Last reset caused by the MENRST circuit 0 = POR or read of SRSR

LVI — Low-Voltage Inhibit Reset Bit

1 = Last reset caused by the LVI circuit

0 = POR or read of SRSR

MC68HC908MR32 • MC68HC908MR16 Data Sheet, Rev. 6.1

192

Freescale Semiconductor

Page 191 Page 193
Page 192
Image 192
Freescale Semiconductor MC68HC908MR32 SIM Reset Status Register, PIN External Reset Bit, Ilop Illegal Opcode Reset Bit
Page 191 Page 193

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.
Top Page Image Contents