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*** CONSTRING.ASM ***
*** ***
*** Author : Andrew Duffy ***
*** Date : November 1992 ***
*** Desc. : This program reads in a string from the keyboard ***
*** (terminated by the character 'Term') and outputs it in ***
*** the opposite case. ***
*** ***
*** ©XCNT, 1992-1994. ***
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*** Includes ***
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include "subrts.h" Included by default anyway
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*** Termination character ***
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Term EQU 13
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*** Main control routine ***
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Main jsr Messages Print initial messages
jsr GetString Read string from keyboard
jsr ConString Convert string and output
rts Exit
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*** Messages routine ***
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Messages movea.l #Instructs,a6 Print text and other messages
jsr OUTSTR Call OUTSTR routine
rts Return to Main
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*** GetString routine ***
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GetString movea.l #Data,a0 Storage address
_GetString2 jsr INCH Call INCH routine
jsr OUTCH Call OUTCH routine
cmp.b #8,d0 Compare with Delete character
beq Delete
move.b d0,(a0)+
cmp.b #Term,d0 Compare with Carriage Return
bne.s _GetString2
jsr CRLF Call CRLF routine
rts Return to Main
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*** ConString routine ***
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ConString movea.l #Data,a0 Restore Storage address
_ConString2 move.b (a0)+,d0
jsr Convert.Case
jsr OUTCH Call OUTCH routine
cmp.b #Term,d0 Check for a carriage return
bne _ConString2
rts Return to main menu
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*** Convert.Case routine ***
*** This routine will convert the case of alphabet characters only in d0, ***
*** returning either a converted character or the original in d0. ***
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Convert.Case cmp.b #'A',d0 Check if character is => A ...
bge _Con.Case1 ... go through to second filter
rts
_Con.Case1 cmp.b #'Z',d0 Check if character is <= Z ...
ble _Con.Case3 ... must be capital so convert
cmp.b #'a',d0 Check if character is => a ...
bge _Con.Case2 ... go through to a third filter
rts
_Con.Case2 cmp.b #'z',d0 Check if character if <= z ...
ble _Con.Case3 ... must be lower so convert
rts
_Con.Case3 eor #$20,d0 Convert character
rts
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*** Delete routine ***
*** The delete key was pressed, delete last character on screen and ***
*** decrease address. ***
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Delete jsr SPACE Call SPACE routine
move.b #8,d0 Put ASCII delete in d0
jsr OUTCH Call OUTCH routine
move.b #' ',-(a0)
bra _GetString2 Continue getting the string
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*** Strings ***
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Instructs dc.b "ConString.asm",13,10,"=============",13,10,13,10
dc.b "Type in a string of text to be converted to the opposite case.",13,10
dc.b "Press <RETURN> when finished :",13,10,13,10,0
even
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*** Storage Area ***
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Data ds.b 200
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*** End of file CONSTRING.ASM. ***
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