for convert binary to decimal with VHDL language i want follow this stage :

See more:

VHDL

for convert binary to decimal with VHDL language i want follow this stage :

S1. Shift the binary number left one bit.
S2. If 8 shifts have taken place, the BCD number is in the
Hundreds, Tens, and Units column.
S3. If the binary value in any of the BCD columns is 5 or greater,
add 3 to that value in that BCD column.
S4. Go to 1

can anybody explain stage 2& 3 for me ... why I should shift left and add with 3 when greater than 4. ??????
thanks