[retroben]

Elementary my dear Watson.

Hex numbers 0-F
0 1 2 3 4 5 6 7 8 9
A B C D E F
10 11 12...

Decimal numbers 0-9
0 1 2 3 4 5 6 7 8 9
10 11 12 13 14 15
16 17 18...

Additionally hex goes A0-FF as well.

Hex
A0=160 (16 x 10 = 160)

Decimal
160=160

Every tens place in hex equals sixteen.

Hex
10=16
16=22
1A=26
20=32 (decimals 16+16=32)

Decimal
10=10
16=16
20=20
22=22
26=26
32=32

Bits are in the same byte of an address.
8bits=1byte with ten placements.

The bits are as follows.

bit0? 0=0 neutral

bit1 1=1
bit2 2=2
bit3 4=4
bit4 8=8
bit5 10=16
bit6 20=32
bit7 40=64
bit8 80=128

bit9? FF=255 maximum (256th number including zero)

It can use any and every mixture of bits.
Example:bits 6,5,and 3 20+10+4=34 (52 in decimal).

00-7F in hex are the positive numbers.
80-FF in hex are the negative numbers.
Couning down from FF.
Examples:
FF= -1
FE= -2

80= -127 (maximum negative)
7F= +127 (maximum positive)

To think,I learned hex all on my own,not in school.