Jack Sparrow's Blog – January 2011 Archive (1)

A table lookup on the PIC16 basically takes the following steps:

• Get the address of index zero of the table
• Add the table index to the address
• Jump to that address

The table itself is a sequence of retlw instructions, which put a value into W and return. (dt and related directives are just assembler shorthand for inserting many retlws.)



A first try at implementing a table lookup thus looks like this:…

Continue