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 Diagrams ................................................................................................................................... 5

6.0 Architectural Overview ................................................................................................................................. 7

6.1 EMI REDUCTION ...................................................................................................................................... 7

6.2 ARCHITECTURE

..................................................................................................................................... 7

6.3 INSTRUCTION SET

................................................................................................................................. 7

6.3.1 Key Instruction Set Features ............................................................................................................... 7

6.3.2 Single Byte/Single Cycle Code Execution

......................................................................................... 7

6.3.3 Many Single-Byte, Multi-Function Instructions .................................................................................... 7

6.3.4 Bit-Level Control .................................................................................................................................. 7

6.3.5 Register Set ......................................................................................................................................... 7

6.4 PACKAGING/PIN EFFICIENCY ................................................................................................................ 7

7.0 Absolute Maximum Ratings ......................................................................................................................... 8

8.0 Electrical Characteristics .............................................................................................................................. 8

9.0 Pin Descriptions ......................................................................................................................................... 11

10.0 Functional Description .............................................................................................................................. 13

10.1 CPU REGISTERS ................................................................................................................................. 13

10.2 PROGRAM MEMORY ........................................................................................................................... 14

10.3 DATA MEMORY .................................................................................................................................... 14

10.4 OPTION REGISTER ............................................................................................................................. 14

10.5 RESET ................................................................................................................................................... 15

10.5.1 External Reset ................................................................................................................................. 15

10.5.2 On-Chip Power-On Reset ................................................................................................................ 15

10.6 OSCILLATOR CIRCUITS ...................................................................................................................... 16

10.6.1 Crystal Oscillator .............................................................................................................................. 16

10.6.2 R/C Oscillator ................................................................................................................................... 16

10.6.3 External Oscillator ............................................................................................................................ 17

10.6.4 Clock Prescaler ................................................................................................................................ 17

10.7 CONTROL REGISTERS ....................................................................................................................... 18

10.7.1 CNTRL Register (Address X'00EE) ................................................................................................. 18

10.7.2 PSW Register (Address X'00EF) ..................................................................................................... 18

10.7.3 ICNTRL Register (Address X'00E8) ................................................................................................ 18

10.7.4 ITMR Register (Address X'00CF) .................................................................................................... 18

11.0 Timers ....................................................................................................................................................... 18

11.1 TIMER T0 (IDLE TIMER) ....................................................................................................................... 18

11.1.1 ITMR Register .................................................................................................................................. 19

11.2 TIMER T1 .............................................................................................................................................. 19

11.3 MODE 1. PROCESSOR INDEPENDENT PWM MODE ....................................................................... 19

11.4 MODE 2. EXTERNAL EVENT COUNTER MODE ................................................................................ 19

11.5 MODE 3. INPUT CAPTURE MODE ......................................................................................................21

11.6 TIMER CONTROL FLAGS .................................................................................................................... 22

12.0 Power Save Modes .................................................................................................................................. 22

12.1 HALT MODE .......................................................................................................................................... 22

12.2 IDLE MODE ........................................................................................................................................... 23

12.3 MULTI-INPUT WAKE-UP ...................................................................................................................... 24

13.0 Interrupts .................................................................................................................................................. 25

13.1 INTRODUCTION ................................................................................................................................... 25

13.2 MASKABLE INTERRUPTS ................................................................................................................... 26

13.3 VIS INSTRUCTION ............................................................................................................................... 27

13.3.1 VIS Execution .................................................................................................................................. 28

13.4 NON-MASKABLE INTERRUPT ............................................................................................................ 29

13.4.1 Pending Flag .................................................................................................................................... 29

13.4.2 Software Trap .................................................................................................................................. 29

13.4.2.1 Programming Example: External Interrupt ................................................................................. 30

13.5 PORT C AND PORT L INTERRUPTS .................................................................................................. 31

13.6 INTERRUPT SUMMARY ....................................................................................................................... 31

14.0 WATCHDOG/Clock Monitor ..................................................................................................................... 31

14.1 CLOCK MONITOR ................................................................................................................................ 32

14.2 WATCHDOG/CLOCK MONITOR OPERATION .................................................................................... 32

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