I need to work with values larger than what can be fit into the 32 bit long available in the compiler. I can store the values in 5 byte arrays, but I need user interaction via a numeric dispaly and keypad. I need to be able to convert value stored in the array to and from decimal ASCII representations. The built in functions don't appear to offer any help as they will not work with values greater than a long. Can anyone show me how I might do the conversion in assembly. I'm thinking about a function similar to atoul()that returns a pointer to an array and another to do the inverse conversion.