Command: mem_set
  
Syntax: 
  mem_set(a1, i1, i2)
  
Description: 
  Set i2 bytes of memory, starting at address a1, to the value 
  of i1.
  
Comments: 
  The low order 8 bits of i1 are actually stored in each byte.
  
  mem_set(a1, i1, i2) is equivalent to: poke(a1, repeat(i1, i2))
  but is much faster.
  
Example: 
     destination = allocate(1000)
              mem_set(destination, ' ', 1000)
 
See Also: 
  mem_copy, peek, poke, allocate, allocate_low
  
