自动化专业单片机英文文献(20000字符)

2021年1月25日发(作者：nks)
Single-chip is an integrated on a single chip a complete computer system. Even though most of his
features in a small chip, but it has a need to complete the majority of computer components: CPU,
memory,
internal
and
external
bus
system,
most
will
have
the
Core.
At
the
same
time,
such
as
integrated communication interfaces, timers, real-time clock and other peripheral equipment. And
now
the
most
powerful
single-chip
microcomputer
system
can
even
voice,
image,
networking,
input and output complex system integration on a single chip. Also known as single-chip MCU
(Microcontroller),
because
it
was
first
used
in
the
field
of
industrial
control.
Only
by
the
single-chip CPU chip developed from the dedicated processor. The design concept is the first by a
large number of peripherals and CPU in a single chip, the computer system so that smaller, more
easily integrated into the complex and demanding on the volume control devices. INTEL the Z80
is one of the first design in accordance with the idea of the processor, From then on, the MCU and
the development of a dedicated processor parted ways. Early single-chip 8-bit or all of the four.
One
of
the
most
successful is
INTEL's
8031,
because
the
performance
of
a
simple
and
reliable
access to a lot of good praise. Since then in 8031 to develop a single-chip microcomputer system
MCS51 series. Based on single-chip microcomputer system of the system is still widely used until
now.
As
the
field
of
industrial
control
requirements
increase
in
the
beginning
of
a
16-bit
single- chip, but not ideal because the price has not been very widely used. After the 90's with the
big
consumer
electronics
product
development,
single-chip
technology
is
a
huge
improvement.
INTEL
i960
Series
with
subsequent
ARM
in
particular,
a
broad
range
of
applications,
quickly
replaced by 32-bit single-chip 16-bit single- chip high-end status, and enter the mainstream market.
Traditional
8-bit
single-chip
performance
has
been
the
rapid
increase
in
processing
power
compared
to
the
80's
to
raise
a
few
hundred
times.
At
present,
the
high-end
32-bit
single-chip
frequency over 300MHz, the performance of the mid-90's close on the heels of a special processor,
while the ordinary price of the model dropped to one U.S. dollars, the most high-end models, only
10 U.S. dollars. Contemporary single-chip microcomputer system is no longer only the bare- metal
environment
in
the
development
and
use
of
a
large
number
of
dedicated
embedded
operating
system is widely used in the full range of single-chip microcomputer. In PDAs and cell phones as
the
core
processing
of
high-end
single-chip
or
even
a
dedicated
direct
access
to
Windows
and
Linux
operating
systems.
More
than
a
dedicated
single-chip
processor
suitable
for
embedded
systems, so it was up to the application. In fact the number
of single-chip is the world's largest
computer. Modern human life used in almost every piece of electronic and mechanical products
will have a single-chip integration. Phone, telephone, calculator, home appliances, electronic toys,
handheld computers and computer accessories such as a mouse in the Department are equipped
with
1-2
single
chip.
And
personal
computers
also
have
a
large
number
of
single-chip
microcomputer in the workplace. Vehicles equipped with more than 40 Department of the general
single-chip, complex industrial control systems and even single-chip may have hundreds of work
at the same time! SCM is not only far exceeds the number of PC and other integrated computing,
even more than the number of human beings.
The 8051 family of
micro controllers is based on an architecture which is highly optimized for
embedded control systems. It is used in a wide variety of applications from military equipment to
automobiles
to
the
keyboard
on
your
PC.
Second
only
to
the
Motorola
68HC11
in
eight
bit
processors
sales,
the
8051
family
of
microcontrollers
is
available
in
a
wide
array
of
variations
from
manufacturers
such
as
Intel,
Philips,
and
Siemens.
These
manufacturers
have
added
numerous features and peripherals to the 8051 such as I2C interfaces, analog to digital converters,
watchdog timers, and pulse width modulated outputs. Variations of the 8051 with clock speeds up
to
40MHz
and
voltage
requirements
down
to
1.5
volts
are
available.
This
wide
range
of
parts
based
on
one
core
makes
the
8051
family
an
excellent
choice
as
the
base
architecture
for
a
company's entire line of products since it can perform many functions and developers will only
have to learn this one platform. The basic architecture consists of the following features: ·
an eight
bit ALU ·
32 descrete I/O pins (4 groups of 8) which can be individually accessed ·
two 16 bit
timer/counters ·
full duplex UART ·
6 interrupt sources with 2 priority levels ·
128 bytes of on
board
RAM
·

separate
64K
byte
address
spaces
for
DA
TA
and
CODE
memory
One
8051
processor cycle consists of twelve oscillator periods. Each of the twelve oscillator periods is used
for a special function by the 8051 core such as op code fetches and samples of the interrupt daisy
chain
for
pending
interrupts.
The
time
required
for
any
8051
instruction
can
be
computed
by
dividing
the
clock
frequency
by
12,
inverting
that
result
and
multiplying
it
by
the
number
of
processor cycles required by the instruction in question. Therefore, if you have a system which is
using an 11.059MHz clock, you can compute the number of instructions per second by dividing
this value by 12. This gives an instruction frequency of 921583 instructions per second. Inverting
this will provide the amount of time taken by each instruction cycle (1.085 microseconds).
The General Situation of AT89C51
Microcontrollers
are
used
in
a
multitude
of
commercial
applications
such
as
modems,
motor-control systems, air conditioner control systems, automotive engine and among others. The
high processing speed and enhanced peripheral set of these microcontrollers make them suitable
for
such
high-speed
event-based
applications.
However,
these
critical
application
domains
also
require that these microcontrollers are highly reliable. The high reliability and low market risks
can be ensured by a robust testing process and a proper tools environment for the validation of
these microcontrollers both at the component and at the system level. Intel Platform Engineering
department developed an object-oriented multi-threaded test environment for the validation of its
AT89C51 automotive microcontrollers. The goals of this environment was not only to provide a
robust
testing
environment
for
the
AT89C51
automotive
microcontrollers,
but
to
develop
an
environment
which
can
be easily
extended
and
reused for
the
validation
of
several
other
future
microcontrollers.
The
environment
was
developed
in
conjunction
with
Microsoft
Foundation
Classes (AT89C51). The paper describes the design and mechanism of this test environment, its
interactions with various hardware/software environmental components, and how to use A
T89C51.
1.1 Introduction The 8-bit AT89C51 CHMOS microcontrollers are designed to handle high-speed
calculations
and
fast
input/output
operations.
MCS
51
microcontrollers
are
typically
used
for
high-speed
event
control
systems.
Commercial
applications
include
modems,
motor-control
systems,
printers,
photocopiers,
air
conditioner
control
systems,
disk
drives,
and
medical
instruments.
The
automotive
industry
use
MCS
51
microcontrollers
in
engine-control
systems,
airbags, suspension systems, and antilock braking systems (ABS). The AT89C51 is especially well
suited
to
applications
that
benefit
from
its
processing
speed
and
enhanced
on-chip
peripheral
functions
set,
such
as
automotive
power-train
control,
vehicle
dynamic
suspension,
antilock
braking,
and
stability
control
applications.
Because
of
these
critical
applications,
the
market
requires a reliable cost-effective controller with a low interrupt latency response, ability

to
service
the
high
number
of
time
and
event
driven
integrated
peripherals
needed
in
real
time
applications, and a CPU with above average processing power in a single package. The financial
and
legal
risk
of
having
devices
that
operate
unpredictably
is
very
high.
Once
in
the
market,
particularly
in
mission
critical
applications
such
as
an
autopilot
or
anti-lock
braking
system,
mistakes are financially prohibitive. Redesign costs can run as high as a $$500K, much more if the
fix means 2 back annotating it across a product family that share the same core and/or peripheral
design flaw. In addition, field replacements of components is extremely expensive, as the devices
are typically sealed in modules with a total value several times that of the component. To mitigate
these problems, it is essential that comprehensive testing of the controllers be carried out at both
the
component
level
and
system
level
under
worst
case
environmental
and
voltage
conditions.
This
complete
and
thorough
validation
necessitates
not
only
a
well- defined
process
but
also
a
proper
environment
and
tools
to
facilitate
and
execute
the
mission
successfully.
Intel
Chandler
Platform
Engineering
group
provides
post
silicon
system
validation
(SV)
of
various
micro-controllers and processors. The system validation process can
be broken into three major
parts. The type of the device and its application requirements determine which types of testing are
performed on the device. 1.2 The A
T89C51 provides the following standard features: 4Kbytes of
Flash, 128 bytes of RAM, 32 I/O lines, two 16-bittimer/counters, a five vector two-level interrupt
architecture,
a
full
duple
serial
port,
on-chip
oscillator
and
clock
circuitry.
In
addition,
the
AT89C51
is
designed
with
static
logic
for
operation
down
to
zero
frequency
and
supports
two
software selectable power saving modes. The Idle Mode stops the CPU while allowing the RAM,
timer/counters, serial port and interrupt sys -tem to continue functioning. The Power-down Mode
saves the RAM contents but freezes the oscillator disabling all other chip functions until the next
hardware reset. 1-3Pin Description VCC Supply voltage. GND Ground. Port 0
：
Port 0 is an 8-bit
open-drain bi-directional I/O port. As an

output port, each pin can sink eight TTL inputs. When 1s are written to port 0 pins, the pins can be
used
as high
impedance
inputs .Port
0
may
also
be
configured
to
be
the
multiplexed
low
order
address/data
bus
during
accesses
to
external
program
and
data
memory.
In
this
mode
P0
has
internal pullups. Port 0 also receives the code bytes during Flash programming, and outputs the
code bytes during program verification. External pullups are required during program verification.
Port 1
：
Port 1 is an 8-bit bi-directional I/O port with internal pullups. The Port 1 output buffers can
sink/source
four
TTL
inputs.
When
1s
are
written
to
Port
1
pins
they
are
pulled
high
by
the
internal pullups and can be used as inputs. As inputs, Port 1 pins that are externally being pulled
low will source current (IIL) because of the internal pullups. Port 1 also receives the low-order
address bytes during Flash programming and verification. Port 2
：
Port 2 is an 8-bit bi-directional
I/O port with internal pullups. The Port 2 output buffers can sink/source four TTL inputs. When 1s
are written to Port 2 pins they are pulled high by the internal pullups and can be used as inputs. As
inputs, Port
2 pins
that are externally
being
pulled
low
will
source
current
(IIL)
because of
the
internal
pullups. Port
2
emits
the
high-order
address
byte
during
fetches
from
external
program
memory and during accesses to Port 2 pins that are externally being pulled low will source current
(IIL) because of the internal pullups. Port 2 emits the high-order address byte during fetches from
external program memory and during accesses to external data memory that use 16-bit addresses
(MOVX@DPTR).
In
this
application,
it
uses
strong
internal
pull- ups
when
emitting
1s.
During
accesses
to
external
data
memory
that
use
8-bit
addresses
(MOVX
@
RI),
Port
2
emits
the
contents of the P2 Special Function Register. Port 2 also receives the high-order address bits and
some
control
signals
during
Flash
programming
and
verification.
Port
3
：
Port
3
is
an
8-bit