MC68HC908GZ8 Datasheet, PDF (255/344 Pages) Motorola, Inc – Microcontrollers

Data Sheet — MC68HC908GZ8
Section 20. System Integration Module (SIM)
20.1 Introduction
This section describes the system integration module (SIM). Together with the
central processor unit (CPU), the SIM controls all microcontroller unit (MCU)
activities. A block diagram of the SIM is shown in Figure 20-1. Table 20-1 is a
summary of the SIM input/output (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:
– Stop/wait/reset/break entry and recovery
– Internal clock control
• Master reset control, including power-on reset (POR) and computer
operating properly (COP) timeout
• Interrupt control:
– Acknowledge timing
– Arbitration control timing
– Vector address generation
• CPU enable/disable timing
• Modular architecture expandable to 128 interrupt sources
Table 20-1 shows the internal signal names used in this section.
MC68HC908GZ8
Freescale Semiconductor
System Integration Module (SIM)
Data Sheet
255