SECTION 3OVERVIEW
This section contains information about the entire modular microcontroller. It lists the
features of each module, shows device functional divisions and pin assignments, sum-
marizes signal and pin functions, discusses the intermodule bus, and provides system
memory maps. Timing and electrical specifications for the entire microcontroller and
for individual modules are provided in APPENDIX A ELECTRICAL CHARACTERIS-
TICS. Comprehensive module register descriptions and memory maps are provided
in APPENDIX D REGISTER SUMMARY.
3.1 MCU Features
The following paragraphs highlight capabilities of each of the microcontroller modules.
Each module is discussed separately in a subsequent section of this user's manual.
3.1.1 System Integration Module (SIM)
3
• External Bus Support
• Programmable Chip-Select Outputs
• System Protection Logic
• Watchdog Timer, Clock Monitor, and Bus Monitor
• System Protection Logic
• PLL System Clock for Low Power Operation
• Background Debugging Mode
3.1.2 Central Processing Unit (CPU32)
• Instruction Set Supports Controller Applications
• 32-Bit Architecture
• Virtual Memory Implementation
• Loop Mode of Instruction Execution
• Table Lookup and Interpolate Instruction
• Improved Exception Handling for Controller Applications
• Trace on Change of Flow
• Hardware Breakpoint Signal, Background Mode
• Fully Static Operation
3.1.3 Queued Serial Module (QSM)
• Serial Communication Interface (SCI), Enhanced Universal Asynchronous Re-
ceiver Transmitter (UART) with Modulus Baud Rate, Parity
• Queued Serial Peripheral Interface (SPI), High Speed Bidirectional Interface, 80-
Byte RAM, Up to 16 Automatic Transfers
• Dual Function I/O Ports
• Continuous Cycling, 8 to 16 Bits per Transfer
MC68331
OVERVIEW
MOTOROLA
3-1
USER’S MANUAL