library IEEE; use IEEE.STD_LOGIC_1164.ALL; USE ieee.numeric_std.all; --this module is for converting a 4 digit BCD number into binary number. --the range of the input in decimal is 0 to 9999. entity ...

Decimal numbers between 100 and 109 would be represented in BCD by the actual number + 156 (26*6). Numbers between 110 and 119 convert to BCD values of the actual number + 156 + 6.