Instruction Set - Samsung S3F84B8 User Manual

S3F84B8_UM_REV 1.00
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INSTRUCTION SET

6.1 OVERVIEW OF INSTRUCTION SET
The SAM8RC instruction set is specifically designed to support large register files that are typical of most SAM8
microcontrollers. The set contains 78 instructions.
6.1.1 KEY FEATURES OF INSTRUCTION SET
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 to the register file)

Decimal adjustment is included in the binary-coded decimal (BCD) operations

16-bit (word) data can be incremented and decremented

Flexible instructions for bit addressing, rotate, and shift operations
6.1.1.1 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. Additionally, bits within a byte are numbered from 7 to 0, where bit 0 is
the least significant (right-most) bit.
6.1.1.2 Register Addressing
To access an individual register, an 8-bit address in the range of 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, refer to Chapter 2, "Address Spaces."
6.1.1.3 Addressing Modes
There are seven explicit addressing modes, namely, Register (R), Indirect Register (IR), Indexed (X), Direct (DA),
Relative (RA), Immediate (IM), and Indirect (IA). For detailed descriptions of these addressing modes, refer to
Chapter 3, "Addressing Modes."
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6 INSTRUCTION SET