Question

Two input capture events occur at counts 0x1037 and 0xFF20 of the free-running counter. How many counts, in decimal have transpired between these two events?
A. 25,891
B. 57, 421
C. 61,161
D. 64, 551

Answer 1

Answer:

The correct answer is C.

Explanation:

You have to do 0xFF20 - 0x1037 but first, you need to convert the counts from hexadecimal base system to decimal base system using this formula:

$N = x_{1} * 16^{0} + x_{2} * 16^{1} + x_{3} * 16^{2} + x_{4} * 16^{3} + ... + x_n 16^{n-1}$, where position of the x₀ is the rightmost digit of the number.

Note:

• A = 10.
• B = 11.
• C = 12.
• D = 13.
• E = 14.
• F = 15.

0xFF20 = 15*16³+15*16²+2*16¹ = 65312

0x1037 = 1*16³+3*16¹+7*16⁰ = 4151

Result: 65312 - 4151 = 61161