I want to thank you all for your tips. I was able to learn something from each post and use the info to get the program to run. The help is greatly appreciated.

Raghu,
I saw the add routine from your page and I'm not sure if I understand properly.

ADD16: NOP
MOV A,@R0 - this loads A with first addend
ADD A,@R1 - second addend is added
MOV top,A - A is copied to new register
INC R0 - point to new addend
INC R1 - "
MOV A,@R0 - load A with third addend
ADDC A,@R1 - add forth addend to A
MOV top+1,A - A is copied to a new register
MOV R0,#top - ??????????

Does "top" represent the low byte register, and "top+1" represent the high byte register? And finally what is the last line doing?

Regards,
Lisa