What is the frequency of the clock that is being as the clock source for the time?

What is the frequency of the clock that is being used as the clock source for the timer? Explanation: The frequency of the clock source for the timer is equal to f/12(where f is the frequency of the crystal).

In this regard, what is the maximum delay generated by the 15 Mhz clock frequency in accordance to a mode 1 operation of the timer?

Maximum count of mode 1 is 65536, hence the maximum time delay that can be generated is 65536 * 1 microsec = 65536 microsec = 65.536 mili- sec.

Also, what is the operation for mode 1? Mode 1 IT operations are focused on legacy applications and systems that are typically found in an organization's on-premise data center.

Also asked, which timer register has both timers in it?

8051 has two timers Timer0 (T0) and Timer1 (T1), both are 16-bit wide. Since 8051 has 8-bit architecture, each of these is accessed by two separate 8-bit registers as shown in the figure below. These registers are used to load timer count.

Is this a valid statement Setb A *?

Explanation: SETB is used to set a bit of a register. A stands for accumulator which is an 8 bit register, so it is an invalid instruction.

What is the time taken by one machine cycle if crystal frequency is 20 megahertz?

What is the time taken by one machine cycle if crystal frequency is 20MHz? Explanation: It will be executed 200*100 times.

How many data lines are there in a 16 * 2 alphanumeric LCD?

eight data lines

When an interrupt is enabled then where does the pointer moves immediately?

1. When an interrupt is enabled, then where does the pointer moves immediately after this interrupt has occurred? Explanation: When an interrupt occurs, then it jumps to a fixed memory location in memory called the interrupt vector table that holds the address of the Interrupt Service Routine.

What are the different modes in which timer 2 can operate?

The only difference between these two modes is the source for incrementing the timer registers.

Timer Mode. In the timer mode, the internal machine cycles are counted.
Counter Mode.
TMOD Register.
Examples.
Mode 0 of Timer/Counter.
Mode 1 of Timer/Counter.
Mode 2 ofTimer/Counter.
Mode 3 of Timer/Counter.

What is the function of T Mod register?

The TMOD register is used to select the operating mode and the timer/counter operation of the timers. The format of TMOD register is, The lower four bits of TMOD register is used to control timer-0 and the upper four bits are used to control timer-1.

What is the maximum number of counts possible for 16 bit timer?

Mode 1 (16-Bit Timer Mode)

TLx is incremented starting from 0 to a maximum 255. Once the value 255 is reached, TLx resets to 0 and then THx is incremented by 1. As being a full 16-bit timer, the timer may contain up to 65536 distinct values and it will overflow back to 0 after 65,536 machine cycles.

When we add two numbers the destination address must always be?

When we add two numbers the destination address must always be. Explanation: DAA command adds 6 to the nibble if any of the nibbles becomes greater than 9. 3.

Why do we need a uln2803 in driving a relay?

Explanation: We need a ULN2803 for driving a relay because the relay coil requires 10mA or more current to be energized. If microcontroller pins are not able to provide sufficient current to drive relays then we need ULN2803 for driving relays.

How high can an 8 bit timer count?

255

How does up down mode in a timer work?

Up/Down Mode: Timer repeatedly counts from Zero up to the value in TACCR0 and back down to zero.

What are the applications of timer?

Timers are used for various applications in circuits or embedded systems such as to generate baud rates, measuring time generating delays and many more.

There are 4 basic operating modes for a timer which are:

ON-Delay Operation.
OFF-Delay Operation.
Flicker Operation.
Interval Operation.

What is a timer module?

The Timer module is an integral part of any microcontroller family. A Timer / Counter module may derive its clock source from the system clock and perform counting operation based on this clock pulse. In this case it is said to work as a timer and perform time measurement operations.

Why do we use timer in microcontroller?

The timer is an important application in Embedded systems, it maintains the timing of an operation in sync with a system clock or an external clock. The timer has so many applications such as measure time generating delays, they can also be used for generating baud rates.

Which mode is used as 8bit auto reload in 8051 timers?

Mode 1: This is a16-bit mode, which means the timer operation completes with maximum clock pulses that “65535”. Mode 2: This mode is an 8-bit auto reload mode, which means the timer operation completes with only “256” clock pulses.

Why prescaler is used in counter and timers?

The purpose of the prescaler is to allow the timer to be clocked at the rate a user desires. For shorter (8 and 16-bit) timers, there will often be a tradeoff between resolution (high resolution requires a high clock rate) and range (high clock rates cause the timer to overflow more quickly).

What are the pipelining stages include?

Explanation: A 3-stage pipelining is used, so instructions are executed in three stages: Fetch, Decode, Execute.

What is the minimum number of cycles required for reset operation?

8051 Reset Circuit

For reset to happen, the reset input pin (pin 9) must be active high for atleast 2 machine cycles. During a reset operation :- Program counter is cleared and it starts from 00H, register bank #0 is selected as default, Stack pointer is initialized to 07H, all ports are written with FFH.

What are the different modes of 8255?

There are two basic operational modes of 8255:

Bit Set/Reset mode (BSR mode).
Input/Output mode (I/O mode).

What is the clock source of the timers?

Explanation: Timer's clock source is the crystal that is applied to the controller. 2. What is the frequency of the clock that is being used as the clock source for the timer? Explanation: The frequency of the clock source for the timer is equal to f/12(where f is the frequency of the crystal).

What should be done if we want to double the baud rate?

There are two ways to increase or double the baud rate of data transfer in the 8051.

Use a higher-frequency crystal.
Change a bit in the PCON register, shown below.

What are the features used Mode 2 in 8255?

What are the features used mode 2 in 8255?

The 8-bit port is bi-directional and additionally a 5-bit control port is available.
Three I/O lines are available at port C, viz PC2-PC0.
Inputs and outputs are both latched.

Are push and pop instructions are a type of call instructions?

Explanation: PUSH and POP instructions are not CALL instructions because in POP and PUSH instructions the pointer does not move to any location specified by its address which is the fundamental of CALL instruction, so it is not a type of CALL instruction.

Which port of 8255 is operated in all 3 modes?

In this mode only port C bits are used for set or reset. If MSB of control word (D7) is 1, PPI works in input-output mode. This is further divided into three modes: Mode 0 –In this mode all the three ports (port A, B, C) can work as simple input function or simple output function.

When 8051 wakes up then 0x00 is loaded to which register?

When 8051 wakes up then 0x00 is loaded to which register? Explanation: When 8051 wakes up, Program Counter (PC) loaded with 0000H. Because of this in 8051 first opcode is stored in ROM address at 0000H. 5.

What is TCON register?

TCON (Timer Control register) TCON is an 8-bit register. Its bits are used for generating interrupts internal or external. The most important bits of the timer TR and TF are also in it. TR (timer run) and TF (timer overflow) bits which we use in almost all over timer applications are in it.

What are handshaking signals in 8255?

Devices that emulate the 8255 protocol support two handshaking signals: Handshake Trigger—Also called Strobe Input (STB) and Acknowledge Input (ACK) Handshake Event—Also called Input Buffer Full (IBF) and Output Buffer Full (OBF)

What is CJNE?

Home » Instructions » CJNE. The CJNE instruction compares the first two operands and branches to the specified destination if their values are not equal. If the values are the same, execution continues with the next instruction.

What is ANL in 8051?

The ANL instruction performs a bitwise logical AND operation between the specified byte or bit operands and stores the result in the destination operand. Note. When this instruction is used to modify an output port, the value used as the port data will be read from the output data latch, not the input pins of the port.

What is the difference between 8031 and 8051?

Digital Electronics :: The 8051 Microcontroller

What is the difference between the 8031 and the 8051? The 8031 has no interrupts. The 8031 is ROM-less. The 8051 has 64 bytes more memory.

Which is the first microcontroller?

Development. One book credits TI engineers Gary Boone and Michael Cochran with the successful creation of the first microcontroller in 1971. The result of their work was the TMS 1000, which became commercially available in 1974.

Why microcontrollers are not called general purpose computers?

Explanation: Microcontrollers are designed to perform dedicated tasks. While designing general purpose computers end use is not known to designers.

Which of the following is bit addressable register?

3. Which of the following is bit-addressable register? Explanation: The registers, accumulator, PSW, B, P0, P1, P2, P3, IP, IE, TCON and SCON are all bit-addressable registers. Explanation: The registers, DPH and DPL are the higher and lower bytes of a 16-bit register DPTR.

What is the order decided by a processor or the CPU of a controller to execute an instruction?

Discussion Forum

Que.	What is the order decided by a processor or the CPU of a controller to execute an instruction?
b.	execute,fetch,decode
c.	fetch,execute,decode
d.	fetch,decode,execute
	Answer:fetch,decode,execute

Which 8051 ports need pull up resistors to function as an I O port?

Port 1. P1 is a true I/O port as it doesn't have any alternative functions as in P0, but this port can be configured as general I/O only. It has a built-in pull-up resistor and is completely compatible with TTL circuits.

Which operator is the most important while assigning any instructions as register?

Discussion Forum

Que.	Which operator is the most important while assigning any instruction as register indirect instruction?
b.	#
c.	@
d.	&
	Answer:@

What is the frequency of the clock that is being as the clock source for the time?

Related Question Answers

Continue Reading

How do you make Caesar salad dressing from scratch?

What is remote PC Suite?

Where is the house you buy in Dawnstar?

What is the frequency of the clock that is being as the clock source for the time?