Related Documents - Intel 386 User Manual

Reserved Bits
Set and Clear
1.4

RELATED DOCUMENTS

The following documents contain additional information that is useful in designing systems that
incorporate the Intel386 EX processor. To order documents, please call Intel Literature Fulfill-
ment (1-800-548-4725 in the U.S. and Canada; +44(0) 1793-431155 in Europe).
Intel386™ EX Embedded Microprocessor datasheet
Intel386™ SX Microprocessor datasheet
Intel386™ SX Microprocessor Programmer's Reference Manual
Intel386™ SX Microprocessor Hardware Reference Manual
Development Tools
Buyer's Guide for the Intel386™ Embedded Processor Family
Intel386™ EX Microprocessor Pin Multiplexing Map
Packaging
You may also want to refer to Standard 1149.1—1990, IEEE Standard Test Access Port and
Boundary-Scan Architecture and its supplement, Standard 1149.1a—1993.
Reserved bits are not used in this device, but they may be used in
future implementations. Follow these guidelines to ensure
compatibility with future devices:
•
Avoid any software dependence on the state of undefined
register bits.
•
Use a read-modify-write sequence to load registers.
•
Mask undefined bits when testing the values of defined bits.
•
Do not depend on the state of undefined bits when storing
undefined bits to memory or to another register.
•
Do not depend on the ability to retain information written to
undefined bits.
The terms set and clear refer to the value of a bit or the act of giving
it a value. If a bit is set, its value is "1"; setting a bit gives it a "1"
value. If a bit is clear, its value is "0"; clearing a bit gives it a "0"
value.
Document Name
GUIDE TO THIS MANUAL
Order Number
272420
240187
240331
240332
272326
272520
272587
240800
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