LZ: RE: string input help

Subject: LZ: RE: string input help
From: Micah/Richard Brodsky <Micahbro@msn.com>
Date: Tue, 26 Nov 96 00:45:00 UT
In-Reply-To: <>
Put 'push HL' before all GET_KEY calls and 'pop HL' after. GET_KEY modifies 
HL.


At least, I think....


--MZB


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From: 	owner-list-zshell@lists.ticalc.org on behalf of Nathan Adams
Sent: 	Sunday, November 24, 1996 9:09 PM
To: 	list-zshell@lists.ticalc.org
Subject: 	LZ: string input help


I've been trying to write a string input routine and have been having some
trouble.  This is my first shot at zshell/asm.  Here is the code that I am
working on:


For size purposes I'm going to change the code.  Let's say I am writing a
program to input the letter t, store it and then print it out somewhere else


;beginning of "t" program


#include "TI-85.H"


.org 0
.db "Input String", 0


TextIn		= $80DF         ;address to store string of t's


Start:
        ld hl,TextIn            ;load hl with address of TextIn
        CALL_(KeyLoop)          ;Input t's
        ld hl,TextIn            ;load hl with address of TextIn
        ld b,5                  ;load b with number of t's to be displayed
        CALL_(DispTxt)          ;Display t's


Waitforkey:                     ;Wait for key to be pressed &amp; return to zshell
        call GET_KEY
        cp 0
        ret nz
        jr Waitforkey        


KeyLoop:
        call GET_KEY            ;get scancode of last key
        cp $0B                  ;compare it with t key scancode
        JUMP_Z(TKey)            ;if they are equal goto TKey
        
        cp $09                  ;compare it with enter key
        ret z                   ;return if equal
        jr KeyLoop


TKey:
	ld (hl),'t'             ;load current address in hl with 't'
	inc hl                  ;increment address in hl       
	ld a,'t'                  
	ROM_CALL(M_CHARPUT)     ;Output 't'
	JUMP_(KeyLoop)          ;jump back to keyloop to input more t's


DispTxt:
       	ld a,(hl)               ;ld a with char in address in hl
	ROM_CALL(M_CHARPUT)     ;display it       
	inc hl                  ;increment address
	djnz DispTxt            ;jump to DispTxt if value in b is not 0
	ret                     ;return if b is 0


.end


When I try to run a program similar to this I can't get the characters to
display correctly.  What I would like to know is what is wrong with this,
how I can fix it and if there is a better way to input strings.


Any help would be greatly appreciated, I've been working on this for hours.


Nathan Adams