Final answer:
To multiplex 'm' data lines, the number of selection lines required is determined by calculating the logarithm base 2 of 'm' and rounding up to the nearest whole number.
Step-by-step explanation:
If you want to multiplex m data lines, you would need a certain number of selection lines. The number of selection lines, often referred to as control lines or address lines, is based on the logarithm to the base 2 of the number of data lines, because each selection line can control 2 states (on or off). This relationship can be expressed as N = log2(m), where 'N' is the number of selection lines needed to multiplex 'm' data lines. To obtain an integer value for N, you round up to the next whole number if the result is not already an integer.
For instance, if you have 16 data lines, you would calculate the number of selection lines as N = log2(16) = 4. Therefore, you would need 4 selection lines to multiplex 16 data lines. Conversely, if you have 20 data lines, you would calculate the number of selection lines as N = log2(20), which would give you a non-integer result. Therefore, you would need to round up the logarithmic result, to determine the number of selection lines required, which would be 5 in this case.