MC912DG128A Motorola, MC912DG128A Datasheet - Page 21

• Manufacturer Part Number: MC912DG128A
• Description: Microcontrollers
• Manufacturer: Motorola

1-cpu12
MOTOROLA
Contents
Introduction
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Programming Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Data Types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Addressing Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Indexed Addressing Modes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Opcodes and Operands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
The CPU12 is a high-speed, 16-bit processing unit. It has full 16-bit data
paths and wider internal registers (up to 20 bits) for high-speed extended
math instructions. The instruction set is a proper superset of the
M68HC11instruction set. The CPU12 allows instructions with odd byte
counts, including many single-byte instructions. This provides efficient
use of ROM space. An instruction queue buffers program information so
the CPU always has immediate access to at least three bytes of machine
code at the start of every instruction. The CPU12 also offers an
extensive set of indexed addressing capabilities.
Central Processing Unit
Central Processing Unit
Central Processing Unit
MC68HC912DT128A Rev 2.0
21