User's Manual
PD789022
PD789024
PD789025
PD789026
PD78F9026A
PD789026 Subseries
8-Bit Single-Chip Microcontrollers
1998
Printed in Japan
Document No.
U11919EJ3V0UMJ1 (3rd edition)
Date Published October 2000 N CP(K)
1996, 1999
User's Manual U11919EJ3V0UM00
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[MEMO]
User's Manual U11919EJ3V0UM00
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SUMMARY OF CONTENTS
CHAPTER 1 GENERAL ....................................................................................................................................23
CHAPTER 2 PIN FUNCTIONS..........................................................................................................................33
CHAPTER 3 CPU ARCHITECTURE.................................................................................................................41
CHAPTER 4 PORT FUNCTIONS......................................................................................................................69
CHAPTER 5 CLOCK GENERATION CIRCUIT ................................................................................................85
CHAPTER 6 16-BIT TIMER ..............................................................................................................................93
CHAPTER 7 8-BIT TIMER/EVENT COUNTER...............................................................................................105
CHAPTER 8 WATCHDOG TIMER ..................................................................................................................115
CHAPTER 9 SERIAL INTERFACE 00 ............................................................................................................121
CHAPTER 10 INTERRUPT FUNCTIONS .........................................................................................................149
CHAPTER 11 STANDBY FUNCTION...............................................................................................................167
CHAPTER 12 RESET FUNCTION ....................................................................................................................175
CHAPTER 13
PD78F9026A............................................................................................................................179
CHAPTER 14 INSTRUCTION SET ...................................................................................................................185
APPENDIX A DEVELOPMENT TOOLS ...........................................................................................................195
APPENDIX B EMBEDDED SOFTWARE..........................................................................................................205
APPENDIX C REGISTER INDEX .....................................................................................................................207
APPENDIX D REVISION HISTORY .................................................................................................................211
User's Manual U11919EJ3V0UM00
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NOTES FOR CMOS DEVICES
1
PRECAUTION AGAINST ESD FOR SEMICONDUCTORS
Note:
Strong electric field, when exposed to a MOS device, can cause destruction of the gate oxide and
ultimately degrade the device operation. Steps must be taken to stop generation of static electricity
as much as possible, and quickly dissipate it once, when it has occurred. Environmental control
must be adequate. When it is dry, humidifier should be used. It is recommended to avoid using
insulators that easily build static electricity. Semiconductor devices must be stored and transported
in an anti-static container, static shielding bag or conductive material. All test and measurement
tools including work bench and floor should be grounded. The operator should be grounded using
wrist strap. Semiconductor devices must not be touched with bare hands. Similar precautions need
to be taken for PW boards with semiconductor devices on it.
2
HANDLING OF UNUSED INPUT PINS FOR CMOS
Note:
No connection for CMOS device inputs can be cause of malfunction. If no connection is provided
to the input pins, it is possible that an internal input level may be generated due to noise, etc., hence
causing malfunction. CMOS devices behave differently than Bipolar or NMOS devices. Input levels
of CMOS devices must be fixed high or low by using a pull-up or pull-down circuitry. Each unused
pin should be connected to V
DD
or GND with a resistor, if it is considered to have a possibility of
being an output pin. All handling related to the unused pins must be judged device by device and
related specifications governing the devices.
3
STATUS BEFORE INITIALIZATION OF MOS DEVICES
Note:
Power-on does not necessarily define initial status of MOS device. Production process of MOS
does not define the initial operation status of the device. Immediately after the power source is
turned ON, the devices with reset function have not yet been initialized. Hence, power-on does
not guarantee out-pin levels, I/O settings or contents of registers. Device is not initialized until the
reset signal is received. Reset operation must be executed immediately after power-on for devices
having reset function.
EEPROM is a trademark of NEC Corporation.
MS-DOS, Windows, and Windows NT are either registered trademarks or trademarks of Microsoft
Corporation in the United States and/or other countries.
IBM DOS, PC/AT, and PC DOS are trademarks of International Business Machines Corporation.
HP9000 series 700 and HP-UX are trademarks of Hewlett-Packard Company.
SPARCstation is a trademark of SPARC International, Inc.
Solaris and SunOS are trademarks of Sun Microsystems, Inc.
OSF/Motif is a trademark of Open Software Foundation, Inc.
NEWS and NEWS-OS are trademarks of Sony Corporation.
TRON is an abbreviation of The Realtime Operating system Nucleus.
ITRON is an abbreviation of Industrial TRON.
User's Manual U11919EJ3V0UM00
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License not needed:
PD78F9026A
The customer must judge the need for license:
PD789022,
PD789024,
PD789025,
PD789026
M8E 00. 4
The information in this document is current as of October, 1999. The information is subject to
change without notice. For actual design-in, refer to the latest publications of NEC's data sheets or
data books, etc., for the most up-to-date specifications of NEC semiconductor products. Not all
products and/or types are available in every country. Please check with an NEC sales representative
for availability and additional information.
No part of this document may be copied or reproduced in any form or by any means without prior
written consent of NEC. NEC assumes no responsibility for any errors that may appear in this document.
NEC does not assume any liability for infringement of patents, copyrights or other intellectual property rights of
third parties by or arising from the use of NEC semiconductor products listed in this document or any other
liability arising from the use of such products. No license, express, implied or otherwise, is granted under any
patents, copyrights or other intellectual property rights of NEC or others.
Descriptions of circuits, software and other related information in this document are provided for illustrative
purposes in semiconductor product operation and application examples. The incorporation of these
circuits, software and information in the design of customer's equipment shall be done under the full
responsibility of customer. NEC assumes no responsibility for any losses incurred by customers or third
parties arising from the use of these circuits, software and information.
While NEC endeavours to enhance the quality, reliability and safety of NEC semiconductor products, customers
agree and acknowledge that the possibility of defects thereof cannot be eliminated entirely. To minimize
risks of damage to property or injury (including death) to persons arising from defects in NEC
semiconductor products, customers must incorporate sufficient safety measures in their design, such as
redundancy, fire-containment, and anti-failure features.
NEC semiconductor products are classified into the following three quality grades:
"Standard", "Special" and "Specific". The "Specific" quality grade applies only to semiconductor products
developed based on a customer-designated "quality assurance program" for a specific application. The
recommended applications of a semiconductor product depend on its quality grade, as indicated below.
Customers must check the quality grade of each semiconductor product before using it in a particular
application.
"Standard": Computers, office equipment, communications equipment, test and measurement equipment, audio
and visual equipment, home electronic appliances, machine tools, personal electronic equipment
and industrial robots
"Special":
Transportation equipment (automobiles, trains, ships, etc.), traffic control systems, anti-disaster
systems, anti-crime systems, safety equipment and medical equipment (not specifically designed
for life support)
"Specific": Aircraft, aerospace equipment, submersible repeaters, nuclear reactor control systems, life
support systems and medical equipment for life support, etc.
The quality grade of NEC semiconductor products is "Standard" unless otherwise expressly specified in NEC's
data sheets or data books, etc. If customers wish to use NEC semiconductor products in applications not
intended by NEC, they must contact an NEC sales representative in advance to determine NEC's willingness
to support a given application.
(Note)
(1) "NEC" as used in this statement means NEC Corporation and also includes its majority-owned subsidiaries.
(2) "NEC semiconductor products" means any semiconductor product developed or manufactured by or for
NEC (as defined above).
The export of these products from Japan is regulated by the Japanese government. The export of some or all of these
products may be prohibited without governmental license. To export or re-export some or all of these products from a
country other than Japan may also be prohibited without a license from that country. Please call an NEC sales
representative.
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