From the department of useless Applesoft routines:

This is something I came up with to do a bitwise XOR
of two 16-bit numbers in pure Applesoft.

Usage: call with A=operand1 and B=operand2, get the
result in X, with A and B destroyed.

10 X = 0 :
   FOR I = 2^16 TO 1 STEP 0 :
   I = I/2 :
   X = X+X+NOT((A>=I)-(B<I)) :
   A = A-I*(A>=I) :
   B = B-I*(B>=I) :
   NEXT :
   RETURN

Paul Guertin
pg@sff.net