R1610C RDC Semiconductor, R1610C Datasheet - Page 21

• Manufacturer Part Number: R1610C
• Description: High Performance 16 Bits MCU Integrated One 10/100M Mac Controller - 3.3V Operating Voltage/2.5V Core Voltage
• Manufacturer: RDC Semiconductor

R
6.
Data Sheet
Final Version 1.5
October 27, 2003
R
6.1 General Registers
6.2 Segment Registers
8-bit registers (AH, AL, BH, BL, CH, CL, DH, and DL). The functions of these registers are described as follows:
addresses (starting location) of these memory segments, and they are immediately addressable for code (CS),
data (DS & ES), and stack (SS) memory.
CS (Code Segment): The CS register points to the current code segment, which contains instruction to be
fetched. The default location memory space for all instructions is 64K. The initial value of CS register is 0FFFFh.
AX: Word Divide, Word Multiply, Word I/O operation.
AH: Byte Divide, Byte Multiply, Byte I/O, Decimal Arithmetic, Translate operation.
AL: Byte Divide, Byte Multiply operation.
BX: Translate operation.
CX: Loops, String operation
CL: Variable Shift and Rotate operation.
DX: Word Divide, Word Multiply, Indirect I/O operation
SP: Stack operations (POP, POPA, POPF, PUSH, PUSHA, PUSHF)
BP: General-purpose registers which can be used to determine offset address of operands in Memory.
SI: String operations
DI: String operations
D
Execution UNIT
D
The R1610C has eight 16-bit general registers. And the AX, BX, CX, and DX can be subdivided into two
R1610C has four 16-bit segment registers: CS, DS, SS, and ES. The segment registers contain the base
C
C
®
®
R
R
I
Index Group
I
S
S
C
C
Group
Data
D
D
Pointer
S
S
P
P
and
C
C
o
o
m
m
m
m
u
u
n
n
i
i
c
c
a
a
t
t
i
i
o
o
n
n
AX
BX
CX
DX
15
GENERAL REGISTERS
High
AH
CH
DH
BH
8
BP
SP
DI
SI
7
Low
AL
CL
DL
BL
0
Count/Loop/Repeat/Shift
Accumulator
Base Register
Data
Stack Pointer
Source Index
Destination Index
Base Pointer
Fast Ethernet RISC Processor
R1610C
21