          SWAPCOLOR      subprogram                            PAGE S16
          -------------------------------------------------------------
 
          Format         CALL SWAPCOLOR(character-set,character-set
                         [,...])
 
                         CALL SWAPCOLOR(#sprite-number,#sprite-number
                         [,...])
 
          Description
 
          The SWAPCOLOR subprogram swaps foreground and background
          colors of the first set with the second set. Or swaps the
          first sprite-number color with the second sprite-number
          color. The character-set numbers are given below:
 
                         set-number          character-codes
                         ~~~~~~~~~~          ~~~~~~~~~~~~~~~
                               0   ----------  30  to   31
                               1   ----------  32  to   39
                               2   ----------  40  to   47
                               3   ----------  48  to   55
                               4   ----------  56  to   63
                               5   ----------  64  to   71
                               6   ----------  72  to   79
                               7   ----------  80  to   87
                               8   ----------  88  to   95
                               9   ----------  96  to  103
                              10   ---------- 104  to  111
                              11   ---------- 112  to  119
                              12   ---------- 120  to  127
                              13   ---------- 128  to  135
                              14   ---------- 136  to  143
          (also sprite table) 15   ---------- 144  to  151
          (also sprite table) 16   ---------- 152  to  159
 
          