15-06-2013, 02:58 PM
MICROCONTROLLER-8051 Features & Applications
[attachment=55478]
Why do we need to learn Microcontrollers ?
Personal information products: Cell phone, pager, watch, pocket recorder, calculator
Laptop components: mouse, keyboard, modem, fax card, sound card, battery charger
Home appliances: door lock, alarm clock, thermostat, air conditioner, TV remote, VCR, small refrigerator, exercise equipment, washer/dryer, microwave oven
Industrial equipment: Temperature/pressure controllers, Counters, timers, RPM Controllers
Toys: video games, cars, dolls, etc.
EVOLUTION
Flashback !!!!
In the year 1976, Motorola created a Microprocessor chip called 6801 which replaced its brother 6800 with certain add-on chips to make a computer. This paved the way for the new revolution in the history of chip design and gave birth to a new entity called
MICROCONTROLLER.
The INTEL bagged the credit of producing the first Microcontroller 8048 with a CPU and 1K bytes of EPROM, 64 Bytes of RAM an 8-Bit Timer and 27 I/O pins in 1976.
ARM Controllers
In recent times ARM company (Advanced Risc machines) has developed and introduced 32 bit controllers which are highend application devices,especially communication devices like mobiles , ipods etc..(Refer www.arm.com)
I/O Port structure
The internal circuitry for the I/O port is shown in the next slide
If you want to read in from a pin, you must first give a logic ‘1’ to the port latch to turn off the FET otherwise the data read in will always be logic ‘0’.
When you write to the port you are actually writing to the latch e.g. a logic 0 given to the latch will be inverted and turn on the FET which cause the port pin to be connected to Gnd (logic 0).
Registers Used in Timer/Counter
8051 has two 16-bit Timer registers ,Timer 0 & Timer 1.
As 8051 has 8-bit architecture , each Timer register is treated as two 8-bit registers namely
TH0, TL0, TH1, TL1.
One 8-bit mode register -TMOD.
One 8-bit control register-TCON.
RxD and TxD pins in the 8051
The 8051 has two pins for transferring and receiving data by serial communication. These two pins are part of the Port3(P3.0 &P3.1)
These pins are TTL compatible and hence they require a line driver to make them RS232 compatible
Max232 chip is one such line driver in use.
Serial communication is controlled by an 8-bit register called SCON register,it is a bit addressable register.
[attachment=55478]
Why do we need to learn Microcontrollers ?
Personal information products: Cell phone, pager, watch, pocket recorder, calculator
Laptop components: mouse, keyboard, modem, fax card, sound card, battery charger
Home appliances: door lock, alarm clock, thermostat, air conditioner, TV remote, VCR, small refrigerator, exercise equipment, washer/dryer, microwave oven
Industrial equipment: Temperature/pressure controllers, Counters, timers, RPM Controllers
Toys: video games, cars, dolls, etc.
EVOLUTION
Flashback !!!!
In the year 1976, Motorola created a Microprocessor chip called 6801 which replaced its brother 6800 with certain add-on chips to make a computer. This paved the way for the new revolution in the history of chip design and gave birth to a new entity called
MICROCONTROLLER.
The INTEL bagged the credit of producing the first Microcontroller 8048 with a CPU and 1K bytes of EPROM, 64 Bytes of RAM an 8-Bit Timer and 27 I/O pins in 1976.
ARM Controllers
In recent times ARM company (Advanced Risc machines) has developed and introduced 32 bit controllers which are highend application devices,especially communication devices like mobiles , ipods etc..(Refer www.arm.com)
I/O Port structure
The internal circuitry for the I/O port is shown in the next slide
If you want to read in from a pin, you must first give a logic ‘1’ to the port latch to turn off the FET otherwise the data read in will always be logic ‘0’.
When you write to the port you are actually writing to the latch e.g. a logic 0 given to the latch will be inverted and turn on the FET which cause the port pin to be connected to Gnd (logic 0).
Registers Used in Timer/Counter
8051 has two 16-bit Timer registers ,Timer 0 & Timer 1.
As 8051 has 8-bit architecture , each Timer register is treated as two 8-bit registers namely
TH0, TL0, TH1, TL1.
One 8-bit mode register -TMOD.
One 8-bit control register-TCON.
RxD and TxD pins in the 8051
The 8051 has two pins for transferring and receiving data by serial communication. These two pins are part of the Port3(P3.0 &P3.1)
These pins are TTL compatible and hence they require a line driver to make them RS232 compatible
Max232 chip is one such line driver in use.
Serial communication is controlled by an 8-bit register called SCON register,it is a bit addressable register.