17-01-2013, 04:45 PM
EMBEDDED SYSTEMS/8051 MICROCONTROLLER
EMBEDDED SYSTEMS.pdf (Size: 681.78 KB / Downloads: 72)
Different types of systems
Open system:
where you can use it for various task.
For e.g.. personal computer.
2. Embedded system:
where you can use it for specific task.it
contains special purpose compute within
the device, and is designed with various
funtions .For e.g. microwave.
EMBEDDED SYSTEMS
Embedded systems are combination of
computer H/W and S/W, and perhaps
additional mechanical or other parts, which
are designed using uP or uC but for a specific
task to perform a dedicated function.
In some cases, ES may be part of a larger
system , as is the case of an anti-lock braking
system in a car.
Some feature that makes 8051
popular
8-bit data bus
16-bit address bus
34 general purpose registers each of 8
bits
16 bit timers (usually 2, but may have
more, or less).
3 internal and 2 external interrupts.
Bit as well as byte addressable RAM area
of 16 bytes.
Four 8-bit ports, (short models have two
8-bit ports).
16-bit program counter and data pointer
TIMER
The 8051 comes equipped with two timers,
both of which may be controlled, set, read,
and configured individually. The 8051 timers
have three general functions:
1) Keeping time and/or calculating the amount
of time between events,
2) Counting the events themselves,
3) Generating baud rates for the serial port.