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Like many early microprocessors it has a 1mhz internal clock for its' operation. 12mhz is divided internally by 12 to derive this frequency.
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What is the purpose of 8051 microcontrollers?
8051 Microcontrollers were popular computer chips used in Intel computers throughout the eighties and nineties. Though technology has advanced beyond their common use, they can still often be found in engineering schools as tools used in introductory microcontroller classes.
Why you use pull up resister at port-0 in 89c51?
Only port 0 needs pull-up resistors to be connected externally if you want to use it as out put port, because it has no in built pull up circuit so it can't give +5v as out put. refer micro controller and applications book by mahmed ali mazidi.
Why you use pull up resistor in microcontroller 8051?
Some devices are internally either in the open drain or in the open collector configuration. So in order to create a closed path for the current the device is pulled up with a resistor to the supply.
Which has higher resistance an ammeter or micro ammeter?
Micro ammeter has higher resistance. use ohm's law.. Say the voltage applied is 1 V. then for the ammeter.. I=1A, V=1V R=1 ohm for the micro ammeter.. I=0.000001, V=1V R=1000000 ohms
What is mean by interrupt service routine?
It is a routine in a micro controllers program where the program jumps to after receiving a interrupt on the micro's interrupt pin. Because most micro's can only run one programme at a time, one need a way for the micro to stop doing what it's busy with, to service an outside peripheral that need urgent attention. For instance the micro is running a flashing LED, a push button that one want to use to stop the flashing and start to flash another LED is connected to the interrupt pin of the micro then the program save what it was busy with on a stag and immediately start the interrupt routine.
Why common cathode connection is used in seven segment display using microcontroller 8051?
The output of 8051 micro controller is active high so we must need to use the common cathode type display . it will work glow when any input is high . The anode terminals of leds's of seven segment connected to 8051's output and cathode is common and grounded . so it require common cathode because 8051 provide active high output.
How we measures strain using microcontroller?
Measuring strain using micro-controller is simple and easy. When measuring using micro-controller you use points and condensers.
What does The device supports throughput of 16 MIPS at 16 MHz mean?
8051 - 8 bit micro based on CISC architecture ( Complex Instruction Set Computer) PIC - 8 bit micro based on RISC architecture ( Reduced Instruction Set Computer)AVR - 8 bit micro based on RISC architecture ( Reduced Instruction Set Computer)there are also 16bit and 32 bit micros from the same familyinvention wise, 8051 is the forefather ( date of birth = 1985), next cam PIC s and then came the AVRs.its essential to learn 8051 to be able to learn other micros. if we come to instruction set of these micros :8051 has 250 instructions which take 1 to 4 machine cycles to executivePIC has nearly 40 instructions which are mostly 4 cycles instructionsAVRs have 140 instructions whcih are mostly 1 cycle basedif we come to speed factor:1 machine cycle in 8051 (normal) divides the clock freq. by 12 ( some derivatives divide by 6 and by 1 also)1 machine cycle in PIC divides the clock freq by 41 M.C in AVRs divides the clock freq by 1for eg: if we use 12 Mhz Xtal in all the 3 micros then the speed of execution will be as follows:8051 = 12Mhz /12 = 1 Mhz i,e = 1 million instructions per secondPIC = 12Mhz/4 = 3 Mhz i,e = 3 million instructions per secondAVR = 12Mhz/1 = 12 MHz i,e = 12 Million instructions per second
Where you can find bootloader for AT89S51?
There is no bootloader available for at89s51(atmel version of 8051)....bcos of absence of bootloader section in at8s51....but u can always use bootloader if u have p89vrs51...this is also an 8051 based controller but it has a bootloader section in it....
Why pullup registers in 8051?
Only port 0 needs pull-up resistors to be connected externally if you want to use it as out put port, because it has no in built pull up circuit so it can't give +5v as out put. refer micro controller and applications book by mahmed ali mazidi.
Why do you use buffer between micro controller and gate driver circuit?
thu ni yankamma
What is mean by registers in micro controller?
Registers are a special type of memory that are dedicated to micro-controllers (or CPUs). Controllers have register-memory for speed.The slowest part of any computer is the bus. The bus is the wiring that connects different components. In this case the micro-controller and main memory. While main memory and the micro-controller are both very fast, the wiring between them is slow.Should the micro-controller have to be slow to compensate for the slow wiring?The solution is to have register-memory. Memory physically part of the micro-controller that allows the controller to use it instantly. The controller can then move data from a register to RAM as soon as the bus is available.Register-memory comes from the concept of a Cash Register [1879]. A cash register is used to perform transactions and store money on it's way to a vault the same way a CPU or micro-controller stores data on its way to main memory.
Safety automation of car project can be carried out using which micro contrller?
One of the least important considerations at the beginning of an automation project is the micro-controller. There are a wide range of them available and they offer a vast array of functionality. The major manufacturers of micro-controllers offer tiny 8 pin devices through 100 pin ICs that have a remarkable set of functions. Before thinking about the micro-controller to use, it is vital that the functional specification of the final product is considered. Without that specification, choosing a micro-controller is nothing more than guess work.
Why the cost of microprocessor is greater than that of a micro controller?
Microprocessors tend to be much faster than microcontrollers. As real time systems usually don't require fast processors the additional power used for the extra speed is seen as wasted. Older boards are also preferred as it is less likely to contain bugs.
In microcontroller 8051 at a time how many timers you can use?
we can use both timers ...
What is dg controler?
DG Controller is a 3-phase Automatic Generator Controller module that includes protection for GENSETS. Use of advanced micro controller in the design platform provides easy and trouble free control and operation mechanism of GENSETS in case of failure of mains power.
How do you add and subtract 16 bit numbers using 8051 microprocessor?
The 8051 is a microcontroller, not a microprocessor. To add or subtract, use the ADD or SUBB opcodes.
