MAIN      START
          RPUSH
                                   ; Init Variables
          LAD       GR1,I002
          XOR       GR2,GR2
          LAD       GR3,258
          CALL      C010
                                   ; Print "Swapcase Alphabet"
          OUT       LB001,LL001
                                   ; Input s
          IN        SB001,SL001
          XOR       GR0,GR0
          ST        GR0,EOF
          LD        GR0,SL001
          JPL       J001
          JZE       J001
          ST        GR0,EOF
          XOR       GR0,GR0
          ST        GR0,SL001
J001      NOP
                                   ; For i = 0 To (Len(s) - 1) Step 1
          LD        GR7,SL001
          LAD       GR7,-1,GR7
          ST        GR7,T001
          XOR       GR7,GR7
          ST        GR7,I002
J002      NOP
          LD        GR1,I002
          CPA       GR1,T001
          JPL       J004
                                   ; If ((s(i) >= "A"c) And (s(i) <= "Z"c)) Then
          LD        GR7,I002
          LD        GR1,GR7
          LD        GR2,SL001
          LAD       GR3,SB001
          CALL      C011
          LD        GR7,GR0
          LD        GR6,='A'
          XOR       GR0,GR0
          CPA       GR7,GR6
          JMI       J011
          LAD       GR0,#FFFF
J011      LD        GR7,GR0
          LD        GR6,I002
          LD        GR1,GR6
          LD        GR2,SL001
          LAD       GR3,SB001
          CALL      C011
          LD        GR6,GR0
          LD        GR5,='Z'
          XOR       GR0,GR0
          CPA       GR6,GR5
          JPL       J012
          LAD       GR0,#FFFF
J012      LD        GR6,GR0
          AND       GR7,GR6
          AND       GR7,GR7
          JZE       J006
                                   ; s( i ) = ((s(i) + "a"c) - "A"c)
          LD        GR7,I002
          LD        GR1,GR7
          LD        GR2,SL001
          CALL      C013
          LAD       GR7,SB001
          ADDL      GR7,GR0
          LD        GR6,I002
          LD        GR1,GR6
          LD        GR2,SL001
          LAD       GR3,SB001
          CALL      C011
          LD        GR6,GR0
          ADDA      GR6,='a'
          SUBA      GR6,='A'
          ST        GR6,0,GR7
          JUMP      J005
                                   ; ElseIf Not(((s(i) < "a"c) Or (s(i) > "z"c))) Then
J006      NOP
          LD        GR7,I002
          LD        GR1,GR7
          LD        GR2,SL001
          LAD       GR3,SB001
          CALL      C011
          LD        GR7,GR0
          LD        GR6,='a'
          LAD       GR0,#FFFF
          CPA       GR7,GR6
          JMI       J013
          XOR       GR0,GR0
J013      LD        GR7,GR0
          LD        GR6,I002
          LD        GR1,GR6
          LD        GR2,SL001
          LAD       GR3,SB001
          CALL      C011
          LD        GR6,GR0
          LD        GR5,='z'
          LAD       GR0,#FFFF
          CPA       GR6,GR5
          JPL       J014
          XOR       GR0,GR0
J014      LD        GR6,GR0
          OR        GR7,GR6
          XOR       GR7,=#FFFF
          AND       GR7,GR7
          JZE       J005
                                   ; s( i ) = ((s(i) + "A"c) - "a"c)
          LD        GR7,I002
          LD        GR1,GR7
          LD        GR2,SL001
          CALL      C013
          LAD       GR7,SB001
          ADDL      GR7,GR0
          LD        GR6,I002
          LD        GR1,GR6
          LD        GR2,SL001
          LAD       GR3,SB001
          CALL      C011
          LD        GR6,GR0
          ADDA      GR6,='A'
          SUBA      GR6,='a'
          ST        GR6,0,GR7
                                   ; End If
J005      NOP
                                   ; Next i
J003      NOP
          LAD       GR1,I002
          LD        GR2,0,GR1
          LAD       GR2,1,GR2
          ST        GR2,0,GR1
          JUMP      J002
J004      NOP
                                   ; Print s
          OUT       SB001,SL001
EXIT      NOP
          RPOP
          RET
                                   ; Dim i As Integer
I002      DS        1
                                   ; Dim s As String
SL001     DS        1
SB001     DS        256
EOF       DS        1
T001      DS        1
LL001     DC        17
LB001     DC        'Swapcase Alphabet'
                                   ; UtilFill
C010      PUSH      0,GR1
          PUSH      0,GR2
          PUSH      0,GR3
          ADDL      GR3,GR1
J015      CPL       GR1,GR3
          JZE       J016
          ST        GR2,0,GR1
          LAD       GR1,1,GR1
          JUMP      J015
J016      POP       GR3
          POP       GR2
          POP       GR1
          RET
                                   ; UtilLoadElement
C011      AND       GR2,GR2
          JNZ       J007
          XOR       GR0,GR0
          RET
J007      CALL      C013
          PUSH      0,GR3
          ADDL      GR3,GR0
          LD        GR0,0,GR3
          POP       GR3
          RET
                                   ; UtilSafeIndex
C013      AND       GR2,GR2
          JNZ       J008
          XOR       GR0,GR0
          RET
J008      LD        GR0,GR1
          JPL       J009
          XOR       GR0,GR0
          RET
J009      CPL       GR0,GR2
          JMI       J010
          LAD       GR0,-1
          ADDL      GR0,GR2
J010      RET
          END