On Sat, 14 Jun 2003, Mike Harrison wrote:
 > For such a small number of values, maybe some trickery can be done to
 > simplfy things, in particular it may be easier to insert new values in
 > the correct place in the list instead of sorting afterwards - a new
 > value cannot affect the order of the other 4 values. Also, it may be
 > easier/quicker to not move the values about, just keep a list of what
 > order they need to be in, as this can be held in one byte per entry, so
 > fewer things need to be juggled about

For such low number of items, bubble sort is the best. You need an
algorithm like (in pseudo C):

#define try_swap(a,b) if( a > b ) { int x=a; a=b; b=x; }

     try_swap(a[0],a[1]);
     try_swap(a[0],a[2]);
     try_swap(a[0],a[3]);
     try_swap(a[0],a[4]);

     try_swap(a[1],a[2]);
     try_swap(a[1],a[3]);
     try_swap(a[1],a[4]);

     try_swap(a[2],a[3]);
     try_swap(a[2],a[4]);

     try_swap(a[3],a[4]);

It's unroled, so you don't really need array access (you can
sort any five variables). To write in PIC assembler, you only
need the "try_swap" macro. If your variables were 8 bit, it
can be done in 6 cicles, so the total is  6*10 = 60 cycles.

     Daniel.

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It's very interesting, i have the same need, but i don't know how to
write it in pic assembler can you help me ?

Thank you

Jean Karl

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