Table of Contents
1.0 General Description ..................................................................................................................................... 1
2.0 Features ....................................................................................................................................................... 1
3.0 Block Diagram .............................................................................................................................................. 2
4.0 Ordering Information .................................................................................................................................... 2
5.0 Connection Diagram .................................................................................................................................... 6
6.0 Architectural Overview ................................................................................................................................. 8
6.1 EMI REDUCTION ...................................................................................................................................... 8
6.2 IN-SYSTEM PROGRAMMING AND VIRTUAL EEPROM ........................................................................ 8
6.3 DUAL CLOCK AND CLOCK DOUBLER ................................................................................................... 8
6.4 TRUE IN-SYSTEM EMULATION .............................................................................................................. 8
6.5 ARCHITECTURE ..................................................................................................................................... 8
6.6 INSTRUCTION SET ................................................................................................................................. 8
6.6.1 Key Instruction Set Features ............................................................................................................... 8
6.6.2 Single Byte/Single Cycle Code Execution ......................................................................................... 8
6.6.3 Many Single-Byte, Multi-Function Instructions .................................................................................... 8
6.6.4 Bit-Level Control .................................................................................................................................. 9
6.6.5 Register Set ......................................................................................................................................... 9
6.7 PACKAGING/PIN EFFICIENCY ................................................................................................................ 9
7.0 Absolute Maximum Ratings ....................................................................................................................... 10
8.0 Electrical Characteristics ............................................................................................................................ 10
9.0 Pin Descriptions ......................................................................................................................................... 15
9.1 EMULATION CONNECTION ................................................................................................................... 16
10.0 Functional Description .............................................................................................................................. 16
10.1 CPU REGISTERS ................................................................................................................................. 16
10.2 PROGRAM MEMORY ........................................................................................................................... 17
10.3 DATA MEMORY .................................................................................................................................... 17
10.4 DATA MEMORY SEGMENT RAM EXTENSION .................................................................................. 17
10.4.1 Virtual EEPROM .............................................................................................................................. 18
10.5 OPTION REGISTER ............................................................................................................................. 18
10.6 SECURITY ............................................................................................................................................ 19
10.7 RESET ................................................................................................................................................... 19
10.7.1 External Reset ................................................................................................................................. 20
10.7.2 On-Chip Brownout Reset ................................................................................................................. 20
10.8 OSCILLATOR CIRCUITS ...................................................................................................................... 21
10.8.1 Oscillator .......................................................................................................................................... 21
10.8.2 Clock Doubler .................................................................................................................................. 22
10.9 CONTROL REGISTERS ....................................................................................................................... 22
10.9.1 CNTRL Register (Address X'00EE) ................................................................................................. 22
10.9.2 PSW Register (Address X'00EF) ..................................................................................................... 22
10.9.3 ICNTRL Register (Address X'00E8) ................................................................................................ 23
10.9.4 T2CNTRL Register (Address X'00C6) ............................................................................................. 23
10.9.5 T3CNTRL Register (Address X'00B6) ............................................................................................. 23
10.9.6 HSTCR Register (Address X'00AF) ................................................................................................ 23
10.9.7 ITMR Register (Address X'00CF) .................................................................................................... 23
10.9.8 ENAD Register (Address X'00CB) .................................................................................................. 23
11.0 In-System Programming ........................................................................................................................... 24
11.1 INTRODUCTION ................................................................................................................................... 24
11.2 FUNCTIONAL DESCRIPTION .............................................................................................................. 24
11.3 REGISTERS .......................................................................................................................................... 24
11.3.1 ISP Address Registers ..................................................................................................................... 24
11.3.2 ISP Read Data Register .................................................................................................................. 24
11.3.3 ISP Write Data Register ................................................................................................................... 24
11.3.4 ISP Write Timing Register ................................................................................................................ 25
11.4 MANEUVERING BACK AND FORTH BETWEEN FLASH MEMORY AND BOOT ROM ..................... 25
11.5 FORCED EXECUTION FROM BOOT ROM ......................................................................................... 26
11.6 RETURN TO FLASH MEMORY WITHOUT HARDWARE RESET ....................................................... 26
11.7 MICROWIRE/PLUS ISP ........................................................................................................................ 26
11.8 USER ISP AND VIRTUAL E2 ................................................................................................................ 27
11.9 RESTRICTIONS ON SOFTWARE WHEN CALLING ISP ROUTINES IN BOOT ROM ....................... 29
11.10 FLASH MEMORY DURABILITY CONSIDERATIONS ........................................................................ 29
12.0 Timers ....................................................................................................................................................... 30
12.1 TIMER T0 (IDLE TIMER) ...................................................................................................................... 30
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