S3F80JB

INSTRUCTION SET

 

 

6 INSTRUCTION SET

OVERVIEW

The SAM8 instruction set is specifically designed to support the large register files that are typical of most SAM8 microcontrollers. There are 78 instructions. The powerful data manipulation capabilities and features of the instruction set include:

A full complement of 8-bit arithmetic and logic operations, including multiply and divide

No special I/O instructions (I/O control/data registers are mapped directly into the register file)

Decimal adjustment included in binary-coded decimal (BCD) operations

16-bit (word) data can be incremented and decremented

Flexible instructions for bit addressing, rotate, and shift operations

Data Types

The SAM8 CPU performs operations on bits, bytes, BCD digits, and two-byte words. Bits in the register file can be set, cleared, complemented and tested. Bits within a byte are numbered from 7 to 0, where bit 0 is the least significant (right-most) bit.

Register Addressing

To access an individual register, an 8-bit address in the range 0-255 or the 4-bit address of a working register is specified. Paired registers can be used to construct 16-bit data or 16-bit program memory or data memory addresses. For detailed information about register addressing, please refer to Section 2, "Address Spaces."

Addressing Modes

There are seven explicit addressing modes: Register (R), Indirect Register (IR), Indexed (X), Direct (DA), Relative (RA), Immediate (IM) and Indirect (IA). For detailed descriptions of these addressing modes, please refer to Section 3, "Addressing Modes."

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Samsung S3F80JB manual Data Types, Addressing Modes