Am186™CC/CH/CU Microcontrollers User’s Manual
2-1
CHAPTER
2
CONFIGURATION BASICS
2.1
OVERVIEW
All members of the Am186 family, including the Am186CC/CH/CU microcontrollers, build
on the same core set of internal processor registers, instructions, and addressing modes.
All members are compatible with the original industry-standard 186 parts.
This chapter provides basic information about configuring the microcontrollers, including
discussions of the registers, memory organization, address generation, I/O space,
peripheral control block, instruction set, segments, data types, and addressing modes.
2.2
REGISTER SET
The microcontroller contains hundreds of configuration and control registers, both internal
and external to the processor. The instruction set contains instructions to access the internal
processor registers directly. Peripheral registers are external to the processor. However,
because the processor treats these peripheral registers either like memory or like I/O,
instructions with memory or I/O operands can access peripheral registers. This section
briefly describes these processor and peripheral registers. For detailed information on the
microcontroller peripheral registers, see the
Am186™CC/CH/CU Microcontrollers Register
Set Manual, order #21916.
2.2.1
Processor Registers
The base architecture of the Am186CC/CH/CU microcontrollers has 14 registers, like all
members of the Am186 family. Table 2-1 lists these registers.
Table 2-1
Internal Processor Registers
Register Name
Register
Mnemonic
Function
General-Purpose
Arithmetic and Logical
Operand
AX
Accumulator
BX
Base
CX
Count
DX
Data
Base Pointer
BP
Stack segment, points to bottom of the stack frame
Source Index
SI
Data movement and string instructions
Destination Index
DI
Stack Pointer
SP
Stack segment, points to top of stack
Code Segment
CS
Points to the current code segment, which contains
instructions to be fetched
Data Segment
DS
Selects memory segment addressable for data
Stack Segment
SS
Selects memory segment addressable for the stack
Extra Segment
ES
Selects memory segment addressable for data
Processor Status Flags
FLAGS
Contains status and control flag bits
Instruction Pointer
IP
Contains offset address of next instruction to be
executed
Summary of Contents for Am186 CC
Page 1: ...Am186 CC CH CU Microcontrollers User s Manual Order 21914B...
Page 4: ...iv Am186 CC CH CU Microcontrollers User s Manual...
Page 18: ...Table of Contents xviii Am186 CC CH CU Microcontrollers User s Manual...
Page 24: ...Introduction xxiv Am186 CC CH CU Microcontrollers User s Manual...
Page 40: ...Architectural Overview 1 16 Am186 CC CH CU Microcontrollers User s Manual...
Page 86: ...System Overview 3 36 Am186 CC CH CU Microcontrollers User s Manual...
Page 92: ...Emulator Support 4 6 Am186 CC CH CU Microcontrollers User s Manual...
Page 112: ...DRAM Controller 6 8 Am186 CC CH CU Microcontrollers User s Manual...
Page 134: ...Interrupts 7 22 Am186 CC CH CU Microcontrollers User s Manual...
Page 186: ...Programmable I O Signals 9 8 Am186 CC CH CU Microcontrollers User s Manual...
Page 200: ...Watchdog Timer 11 6 Am186 CC CH CU Microcontrollers User s Manual...
Page 232: ...Asynchronous Serial Ports UARTs 13 24 Am186 CC CH CU Microcontrollers User s Manual...
Page 242: ...Synchronous Serial Port SSI 14 10 Am186 CC CH CU Microcontrollers User s Manual...
Page 264: ...High Level Data Link Control HDLC 15 22 Am186 CC CH CU Microcontrollers User s Manual...
Page 332: ...Universal Serial Bus USB 18 34 Am186 CC CH CU Microcontrollers User s Manual...
Page 348: ...Register Summary A 16 Am186 CC CH CU Microcontrollers User s Manual...
Page 376: ...Index Index 18 Am186 CC CH CU Microcontrollers User s Manual...