2 introduction, Introduction – Freescale Semiconductor MC68HC08KH12 User Manual
Page 62

Advance Information
MC68HC(7)08KH12
—
Rev. 1.1
62
Freescale Semiconductor
Low-Power Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79
Wait Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80
Stop Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81
SIM Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83
Break Status Register (BSR). . . . . . . . . . . . . . . . . . . . . . . . 83
Reset Status Register (RSR) . . . . . . . . . . . . . . . . . . . . . . . 84
Break Flag Control Register (BFCR). . . . . . . . . . . . . . . . . . 85
7.2 Introduction
This section describes the system integration module (SIM), which
supports up to 24 external and/or internal interrupts. Together with the
CPU, the SIM controls all MCU activities. A block diagram of the SIM is
shown in
is a summary of the SIM I/O registers.
The SIM is a system state controller that coordinates CPU and exception
timing. The SIM is responsible for:
•
Bus clock generation and control for CPU and peripherals
–
top/wait/reset/break entry and recovery
–
Internal clock control
•
Master reset control, including power-on reset (POR) and COP
timeout
•
Interrupt control:
–
Acknowledge timing
–
Arbitration control timing
–
Vector address generation
•
CPU enable/disable timing
•
Modular architecture expandable to 128 interrupt sources