What is MUL AB?
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What is MUL AB?
The MUL instruction multiplies the unsigned 8-bit integer in the accumulator and the unsigned 8-bit integer in the B register producing a 16-bit product. The high-order byte of the product is returned in the B register. The OV flag is set if the product is greater than 255 (0FFh), otherwise it is cleared.
What is the function of MUL AB instruction?
The MUL AB instruction multiplies the Accumulator by the data in the B register and puts the 16- bit product into the concatenated B and Accumulator registers.
What is the time taken by 8051 to execute the instruction MUL AB which takes 4 machine cycles?
In the 8051, one machine cycle lasts 12 oscillator periods. So to calculate the machine cycle, we take 1/12 of the crystal frequency, then take the inverse of it results in time period….SECTION – III TIME DELAY CALCULATION IN 8051.
| INSTRUCTION | MACHINE CYCLE | TIME TO EXECUTE |
|---|---|---|
| MOV R2,#55H | 1 | 1×1.085 us = 1.085 us |
| MUL AB | 4 | 4×1.085 us = 4.34 us |
How much total external data memory that can be interfaced to the 8051?
While Internal RAM is limited to 128 bytes (256 bytes with an 8052), the 8051 supports External RAM up to 64K. Programming Tip: The 8051 may only address 64k of RAM.
What is mul CL?
1. Your source is 8 bits ( cl ) so the multiplication is performed over al only. Use mul cx instead. Explanation: If ax = 100h , then al = 00h . Since the result of mul cl is placed in ax , what you do is basically to replace the content of ax with 00h*cl , which is 00h .
How do you square a number in 8051?
Algorithm:
- Initialize R0 with memory address where all squares are stored and R1 with 0.
- Increment R1 to find the square of a number.
- Find the square of a number by multiplying A and B with same number.
- Store the result with the assigned address array.
How many timers are there in 8051?
two timers
The 8051 has two timers, Timer 0 and Timer 1. They can be used as timers or as event counters. Both Timer 0 and Timer 1 are 16-bit wide. Since the 8051 follows an 8-bit architecture, each 16 bit is accessed as two separate registers of low-byte and high-byte.