59 lines
835 B
NASM
59 lines
835 B
NASM
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subttl -
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;;
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;;FUNCTION: Sets and returns switch char-
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;; acter and device availability.
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;;
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;;
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;;CALL:
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;;
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;; ret= _charop(al,dl)
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;; int ret; DL return value,
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;; int al; charoper function
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;; int dl; charoper data
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;;
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;;RETURN:
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;; See the DOS docs for details.
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;;_charop(0,0) returns the ASCII switch char,
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;;_charop(1,'-') sets the switch to -,
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;;_charop(2,0) returns device availability,
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;;_charop(3,i) sets device availability.
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;;
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;;
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;;DESCRIPTION:
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;;
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;;EXAMPLE:
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;;
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;;
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;;CAUTIONS:
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;;
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;;
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;;ASSUMPTIONS:
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;;
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;;LONG 32 bits (4 bytes)
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;;INT 16 bits (2 bytes)
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;;CHAR 8 bits (1 byte)
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;;
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page
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pgroup group prog
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prog segment byte public 'prog'
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assume cs:pgroup,ds:pgroup
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public _charop
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_charop proc near
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push bp
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mov bp,sp
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mov al,[bp+4]
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mov dl,[bp+6]
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mov ah,55
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int 33
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mov al,dl
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mov ah,0
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pop bp
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ret
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_charop endp
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prog ends
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end
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