# print string in reverse order
       Z0:0 Z1:0 start
       .include lib.bbj
       :mem:0 0 0
       m0:mem m:mem
       x:0 Z:0 m1:-1
 start: .copy m1 x
       .in x
       .ifeq x m1 next store
 store: .toref x m
       .out x
       .add m BASE m
       0 0 start
 next: .sub m BASE m
       .deref m x
       .out x
       .ifeq m m0 -1 next