Samsung C8278X ユーザーズマニュアル

The SAM88RC 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 

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. 

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."   

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."