Intel 8XC196NT, User Manual

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CONTENTS
CHAPTER 4
MEMORY PARTITIONS
4.1 MEMORY MAP OVERVIEW.......................................................................................... 4-1
4.2 MEMORY PARTITIONS ................................................................................................ 4-3
4.2.1 External Memory .......................................................................................................4-5
4.2.2 Program and Special-purpose Memory ....................................................................4-5
4.2.2.1 Program Memory in Page FFH ............................................................................4-5
4.2.2.2 Special-purpose Memory .....................................................................................4-6
4.2.2.3 Reserved Memory Locations ...............................................................................4-7
4.2.2.4 Interrupt and PTS Vectors ....................................................................................4-7
4.2.2.5 Security Key .........................................................................................................4-7
4.2.2.6 Chip Configuration Bytes .....................................................................................4-8
4.2.3 Special-function Registers (SFRs) ............................................................................4-8
4.2.3.1 Memory-mapped SFRs ........................................................................................4-8
4.2.3.2 Peripheral SFRs ...................................................................................................4-9
4.2.4 Internal RAM (Code RAM) ......................................................................................4-11
4.2.5 Register File ............................................................................................................4-12
4.2.5.1 General-purpose Register RAM .........................................................................4-13
4.2.5.2 Stack Pointer (SP) ..............................................................................................4-13
4.2.5.3 CPU Special-function Registers (SFRs) .............................................................4-14
4.3 WINDOWING............................................................................................................... 4-15
4.3.1 Selecting a Window ................................................................................................4-16
4.3.2 Addressing a Location Through a Window .............................................................4-17
4.3.2.1 32-byte Windowing Example ..............................................................................4-19
4.3.2.2 64-byte Windowing Example ..............................................................................4-19
4.3.2.3 128-byte Windowing Example ............................................................................4-19
4.3.2.4 Unsupported Locations Windowing Example .....................................................4-20
4.3.2.5 Using the Linker Locator to Set Up a Window ....................................................4-20
4.3.3 Windowing and Addressing Modes .........................................................................4-22
4.4 REMAPPING INTERNAL OTPROM (87C196NT ONLY) ............................................ 4-23
4.5 FETCHING CODE AND DATA IN THE 1-MBYTE AND 64-KBYTE MODES.............. 4-24
4.5.1 Fetching Instructions ...............................................................................................4-24
4.5.2 Accessing Data .......................................................................................................4-24
4.5.2.1 Using Extended Instructions ..............................................................................4-25
4.5.3 Code Fetches in the 1-Mbyte Mode ........................................................................4-26
4.5.4 Code Fetches in the 64-Kbyte Mode ......................................................................4-26
4.5.5 Data Fetches in the 1-Mbyte and 64-Kbyte Modes .................................................4-27
4.6 MEMORY CONFIGURATION EXAMPLES ................................................................. 4-28
4.6.1 Example 1: A 64-Kbyte Mode 87C196NT System ..................................................4-28
4.6.2 Example 2: A 64-Kbyte 87C196NT System with Additional Data Storage ..............4-30
4.6.3 Example 3: A 1-Mbyte 87C196NT System with a 16-bit Bus ..................................4-32
4.6.4 Example 4: A 1-Mbyte 8XC196NT System with an 8-bit Bus .................................4-34