Going from Hex To Dec with PIC18?

Question

I have a little issue trying to combine 4 digits together to give me the correct decimal value. First let me start with my code.

long firsttwo, secondtwo, combined; 
firsttwo = 0x0C;
secondtwo = 0x6C;

The Decimal value of 0C : 12

The Decimal value of 6C : 108

But the Decimal value of all 0C6C : 3180

Now how do I get all the digits into one variable to be able to convert it to decimal correctely? Because if I just convert firsttwo by itself then secondtwo by itself I don't get the same final total. Thanks!

Answer 1

You need to shift the most significant byte when combining:

combined = (firsttwo << 8) | secondtwo;

this sets combined to 0x0c6c.