EM78P451S
8-Bit Microcontroller
with OTP ROM
Product
Specification
D
OC
. V
ERSION
1.0
ELAN MICROELECTRONICS CORP.
June 2004
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are trademarks of ELAN Microelectronics Corporation.
Copyright
2005 by ELAN Microelectronics Corporation
All Rights Reserved
Printed in Taiwan
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responsibility concerning the accuracy, adequacy, or completeness of this specification. ELAN Microelectronics makes
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information and material may change to conform to each confirmed order.
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ELAN MICROELECTRONICS CORPORATION
Headquarters:
No. 12, Innovation Road 1
Hsinchu Science Park
Hsinchu, Taiwan 30077
Tel: +886 3 563-9977
Fax: +886 3 563-9966
http://www.emc.com.tw
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Elan (HK) Microelectronics
Corporation, Ltd.
Rm. 1005B, 10/F Empire Centre
68 Mody Road, Tsimshatsui
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elanhk@emc.com.hk
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Elan Information
Technology Group
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Saratoga, CA 95070
USA
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Elan Microelectronics Corp.
(Europe)
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8050 Zurich, SWITZERLAND
Tel: +41 43 299-4060
Fax: +41 43 299-4079
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Shenzhen:
Elan Microelectronics
Shenzhen, Ltd.
SSMEC Bldg., 3F, Gaoxin S. Ave.
Shenzhen Hi-Tech Industrial Park
Shenzhen, Guandong, CHINA
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Shanghai Corporation, Ltd.
23/Bldg. #115 Lane 572, Bibo Road
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Fax: +86 021 5080-4600
Contents
Product Specification (V1.0) 06.01.2004
iii
Contents
1 GENERAL
DESCRIPTION................................................................................................... 1
2 FEATURES........................................................................................................................... 1
3 PIN
ASSIGNMENT ............................................................................................................... 2
4 FUNCTION
DESCRIPTION.................................................................................................. 4
4.1 Operational
Registers ..................................................................................................4
4.1.1 R0
(Indirect
Address Register) ...................................................................................... 4
4.1.2 R1
(TCC) ....................................................................................................................... 4
4.1.3 R2
(Program
Counter) & Stack...................................................................................... 4
4.1.4 R3
(Status Register) ...................................................................................................... 6
4.1.5 R4 (RAM Select Register) ............................................................................................. 6
4.1.6 R5~R8
(Port 5 ~ Port8).................................................................................................. 7
4.1.7 R9
(Port9) ...................................................................................................................... 7
4.1.8 RA (SPIRB: SPI Read Buffer)........................................................................................ 8
4.1.9 RB (SPIWB: SPI Write Buffer)....................................................................................... 8
4.1.10 RC (SPIS: SPI Status Segister)..................................................................................... 8
4.1.11 RD (SPIC: SPI Control Register)................................................................................... 9
4.1.12 RE (TMR1: Timer1 register) ........................................................................................ 10
4.1.13 RF (PWP: Pulse width preset register)........................................................................ 10
4.1.14 R20~R3E (General Purpose Register)........................................................................ 10
4.1.15 R3F (Interrupt Status Register) ................................................................................... 10
4.2 Special Purpose Registers .........................................................................................10
4.2.1 A
(Accumulator) ........................................................................................................... 10
4.2.2 CONT
(Control Register) ............................................................................................. 11
4.2.3 IOC5 ~ IOC9 (I/O Port Control Register)..................................................................... 11
4.2.4 IOCC
(T1CON:
Timer1
control register) ...................................................................... 11
4.2.5 IOCD
(Pull-high
Control Register) ............................................................................... 12
4.2.6 IOCE
(WDT
Control Register) ..................................................................................... 12
4.2.7 IOCF
(Interrupt Mask Register) ................................................................................... 13
4.3 TCC/WDT
Presacler ..................................................................................................14
4.4 I/O
Ports .....................................................................................................................15
4.5 SERIAL PERIPHERAL INTERFACE MODE..............................................................17
4.5.1 Overview
& Features ................................................................................................... 17
4.5.2 SPI
Function
Description............................................................................................. 19
4.5.3 SPI Signal & Pin Description ....................................................................................... 20
4.5.4 Programmed the related registers............................................................................... 22
4.5.5 SPI
Mode Timing ......................................................................................................... 24
4.5.6 Software
Application of SPI ......................................................................................... 25
4.6 Timer
1 .......................................................................................................................30
4.6.1 Overview...................................................................................................................... 30
4.6.2 Function
description .................................................................................................... 30
Contents
iv
Product Specification (V1.0) 06.01.2004
4.6.3 Programmed the related registers............................................................................... 30
4.7 RESET
and
Wake-up .................................................................................................31
4.8 Interrupt......................................................................................................................37
4.9 Oscillator ....................................................................................................................38
4.9.1 Oscillator Modes.......................................................................................................... 38
4.9.2 Crystal
Oscillator/Ceramic Resonators (XTAL) ........................................................... 38
4.9.3 RC
Oscillator Mode ..................................................................................................... 40
4.10 Code Option Register.................................................................................................41
4.11 Instruction Set ............................................................................................................42
4.12 Timing Diagrams ........................................................................................................45
5 ABSOLUTE
MAXIMUM
RATING ....................................................................................... 46
6 ELECTRICAL
CHARACTERISTICS.................................................................................. 46
6.1 DC
Characteristic .......................................................................................................46
6.2 AC
Characteristic .......................................................................................................47
7 Application
Circuit ............................................................................................................ 48
APPENDIX
A Package
Types .................................................................................................................. 49
B Package
Information......................................................................................................... 49
Specification Revision History
Doc. Version
Revision Description
Date
1.0 Initial
version
06/01/2004
EM78P451S
8-Bit Microcontroller with OTP ROM
Product Specification (V1.0) 06.01.2004
1
(This specification is subject to change without further notice)
1 GENERAL
DESCRIPTION
The EM78P451S is an 8-bit microprocessor designed and developed with low-power,
high speed CMOS technology. Its operational kernel is implemented with RISC-like
architecture and is available in the mask ROM version. The one time programmable
(OTP) version is flexible, both in mass production or engineering test stages. OTP
provide users with unlimited volume with favorable price opportunities. This device is
equipped with the Serial Peripheral Interface (SPI) function. The EM78P451S is very
suitable for wired communication. Only 58 easy-to-learn instructions are needed and
user's program can be emulated with EMC In-Circuit Emulator (ICE).
2 FEATURES
Operating voltage range: 2.3V~5.5V.
Operating temperature range: 0
C~70
C.
Operating frequency range (base on 2 clocks ):
Crystal mode: DC~20MHz at 5V, DC~8MHz at 3V, DC~4MHz at 2.3V.
RC mode: DC~4MHz at 5V, DC~4MHz at 3V, DC~4MHz at 2.3V.
Low power consumption:
Less then 3 mA at 5V/4MHz
Typically 10
A during sleep mode
Serial Peripheral Interface (SPI) available.
4K
13 bits on chip ROM (EM78P451S).
11 special function registers.
140
8 bits on chip general-purposed registers.
5 bi-directional I/O ports (35 I/O pins).
3 LED direct sinking pins with internal serial resistors.
Built-in RC oscillator with external serial resistor, 10% variation.
Built-in power-on reset.
5 stacks for subroutine nesting.
8-bit real time clock/counter (TCC) with overflow interrupt.
Two machine clocks or four machine clocks per instruction cycle.
Power down mode.
Programmable wake up from sleep circuit on I/O ports.
Programmable free running on-chip watchdog timer.
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