Final answer:
The time taken to execute the program is 0.5 microseconds. The given assembly program for an 8051 microcontroller with a clock frequency of 8MHz would take 2.625 microseconds to execute.
Step-by-step explanation:
The time taken to execute the given program can be calculated using the formula:
Time = Number of Instructions × Clock Cycle Time
In this case, there are 4 instructions: MOV R2, #10, MOV R1, #25, WAIT, and DJNZ R2, WAIT.
The clock frequency mentioned is 8MHz, which means that the clock cycle time is 1/8MHz = 0.125 microseconds.
Therefore, the time taken to execute the program can be calculated as:
Time = 4 × 0.125 microseconds = 0.5 microseconds.
The given assembly program for an 8051 microcontroller with a clock frequency of 8MHz would take 2.625 microseconds to execute. This calculation considers the machine cycle time of the 8051 and counts the cycles per instruction and the iterations of the loop in the program.
The question is asking about the execution time of a small assembly program on an 8051 microcontroller with a clock frequency of 8MHz. To calculate the execution time, we need to understand the instruction cycle times for this microcontroller and the structure of the given program.
For the 8051, with a clock frequency of 8MHz, one machine cycle is typically 1/8MHz or 0.125 microseconds (since one machine cycle is typically 12 clock cycles for an 8051 microcontroller). However, this can vary depending on the specific variant of the 8051 being used.
The first two instructions, MOV R2, #10 and MOV R1, #25, are each one machine cycle because moving data typically takes one machine cycle.
The instruction DJNZ R2, WAIT is a decrement and jump instruction which takes two machine cycles to execute if the jump is taken. The loop's construct will cause the DJNZ instruction to execute 10 times because R2 is initialized to 10. For the first 9 times, 2 machine cycles are used, and for the last execution, since the jump is not taken, only 1 machine cycle is used.
Calculating this gives us: 2 MOV instructions * 1 machine cycle/instruction + 9 iterations * 2 machine cycles/iteration + 1 final iteration * 1 machine cycle = 2 + 18 + 1 = 21 machine cycles in total.
Now, let's calculate the total execution time: 21 machine cycles * 0.125 microseconds/machine cycle = 2.625 microseconds in total to execute the program.