How to enumerate the position of a bit within a byte?
Where to start putting an ordinal numbering on a given byte, do I start counting the most significant(the left )or the least significant (the right)?
For example for the decimal number 128 that has binary reprint:
1000 0000
If I want to refer to the eighth bit of the byte, who is the digit in question?
1 or 0 ?
Be Mode A or mode B?
Mode A
1000 0000
8765 4321
Mode B
1000 0000
1234 5678
1 answers
The mode to would be the correct one.
Ignore the name bit - a binary value is represented in the same way as a decimal value: in an integer the highest value positions are located on the left, since new positions are added When the previous position suffers overflow :
8 + 1 // 9: Uma casa decimal
9 + 1 // 10: Não pode ser contido em apenas uma posição,
10 // casa decimal 2 recebe o valor em overflow.
...
98 + 1 // 99: Duas casas decimais
99 + 1 // 100: Não pode ser contido em apenas duas posições,
100 // casa decimal 3 recebe o valor em overflow.
Like this:
128 = 100 + 20 + 8
In the example above we can say that the position (house) 3 has the value 1, which means 100 in decimal.
In binary the value
1000 0000
Has the value 1 at position 8, which also means 128 (2 to 7A power).