>I think it would be better to keep the buffer itself as the
>last member of the struct. This way it would be easier to
>make generic functions to deal with FIFOs of different physical
>lengths (physical length could be a field also). Just pass a
>pointer to the FIFO struct to the functions Insert and Remove
>and the same functions may work on several different FIFOs.

This exactly what I have done with the code that I posted the link to. 
Because of the way the tutorial is built up, the code presented has the data 
field first, but because I needed some FIFOs of different size to others, I 
changed it as mentioned above, and included a size field.

>I always try to use FIFO lengths of powers of two, it is easier
>to cope with wrap-around and you don't need to keep Insertion
>index, Remotion index and Length.

Good point, although I don't know how much code is generated for the modulus 
operation that this code uses.

>For FIFOs where the interrupt inserts and the application removes
>I use only the Insert index and length, and for FIFOs where the
>interrupt removes and the application inserts I use Remove index
>and length. This way the interrupt code deals with the simpler
>(faster) operations (inserting in a FIFO with insertion index
>and length, or removing from a FIFO with remotion index and length).

Good thought, but it does require having two sets of routines. I guess 
IsEmpty and IsFull routines work with both, without requiring different 
routines.

I'll be keeping a copy of your routines for future reference though. 

-- 
http://www.piclist.com PIC/SX FAQ & list archive
View/change your membership options at
http://mailman.mit.edu/mailman/listinfo/piclist