UPD784020 Datasheet, PDF (4/90 Pages) NEC – 16/8-BIT SINGLE-CHIP MICROCOMPUTER

CONTENTS
mPD784020, 784021
1. DIFFERENCES BETWEEN mPD784026 SUB-SERIES ........................................................... 6
2. MAIN DIFFERENCES BETWEEN mPD784026 AND mPD78234 SUB-SERIES ..................... 7
3. PIN CONFIGURATION (TOP VIEW) ........................................................................................ 8
4. SYSTEM CONFIGURATION EXAMPLE (PPC) ....................................................................... 10
5. BLOCK DIAGRAM ..................................................................................................................... 11
6. LIST OF PIN FUNCTIONS ........................................................................................................ 12
6.1 PORT PINS ...................................................................................................................................... 12
6.2 NON-PORT PINS ............................................................................................................................ 13
6.3 I/O CIRCUITS FOR PINS AND HANDLING OF UNUSED PINS ................................................. 15
7. CPU ARCHITECTURE .............................................................................................................. 18
7.1 MEMORY SPACE ........................................................................................................................... 18
7.2 CPU REGISTERS ............................................................................................................................ 21
7.2.1 General-Purpose Registers .......................................................................................... 21
7.2.2 Control Registers ........................................................................................................... 22
7.2.3 Special Function Registers (SFRs) ............................................................................. 23
8. PERIPHERAL HARDWARE FUNCTIONS ............................................................................... 28
8.1 PORTS ............................................................................................................................................. 28
8.2 CLOCK GENERATOR .................................................................................................................... 29
8.3 REAL-TIME OUTPUT PORT .......................................................................................................... 31
8.4 TIMERS/COUNTERS ...................................................................................................................... 32
8.5 PWM OUTPUT (PWM0, PWM1) ..................................................................................................... 34
8.6 A/D CONVERTER ........................................................................................................................... 35
8.7 D/A CONVERTER ........................................................................................................................... 36
8.8 SERIAL INTERFACE ...................................................................................................................... 37
8.8.1 Asynchronous Serial Interface/Three-Wire Serial I/O (UART/IOE) ......................... 38
8.8.2 Synchronous Serial Interface (CSI) ............................................................................. 40
8.9 EDGE DETECTION FUNCTION ..................................................................................................... 41
8.10 WATCHDOG TIMER ....................................................................................................................... 42
9. INTERRUPT FUNCTION ........................................................................................................... 43
9.1 INTERRUPT SOURCE .................................................................................................................... 43
9.2 VECTORED INTERRUPT ............................................................................................................... 45
9.3 CONTEXT SWITCHING .................................................................................................................. 46
9.4 MACRO SERVICE ........................................................................................................................... 46
9.5 EXAMPLES OF MACRO SERVICE APPLICATIONS .................................................................. 47
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