$� Demonstrate how to wordwrap in
� assembler
:
(� wrap% &100
2$osnl=&FFE7:osas=&FFE3:oswc=&FFEE
<OaddrL=&70:addrH=&71:� Hi and low bytes of the address where the text starts
Foldpos=&72
P:
Z�X=0�3�3
dP%=wrap%
n	[OPTX
x.getstring
�(\Start at the end and work backwards
�8LDY#39:\Offset 39 is the end of the 40 column screen
�.getletter
�KLDA(addrL),Y:CMP#�"0":BCCwrappointfound:DEY:BMInowrappoint:JMPgetletter
�:
�.wrappointfound
�7\Might still be (or might be) a carriage return too
�INY:STYoldpos:LDY#0
�.carriagesearch
�FLDA(addrL),Y:CMP#13:BEQcarriagereturn:INY:CPY#40:BNEcarriagesearch
�LDAoldpos:JSRprintitthen
�6LDAoldpos:CMP#40:BEQgetstring:JSRosnl:JMPgetstring
�EQUS"(C)1998 SPROW"

:

.carriagereturn

#\Print upto the carriage return

"'INY:TYA:JSRprintitthen:JMPgetstring

,:

6.nowrappoint

@3\Just print out 40 letters cos we couldn't wrap

J&LDA#40:JSRprintitthen:JMPgetstring

T:

^.printitthen

h'\Prints out 'n' chrs specified in A

rLDY#0:TAX:DEX

|.printloop

�=LDA(addrL),Y:BEQprintjobdone:JSRoswc:INY:DEX:BPLprintloop

�
.printadd

�TYA:CLC:ADCaddrL:STAaddrL

�FLDA#0:ADCaddrH:STAaddrH:RTS:\Bump up the address by 'n' characters

�.printjobdone

�2PLA:PLA:RTS:\Suck off top stack entry and quit

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��text% 5000

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00000010  65 20 68 6f 77 20 74 6f  20 77 6f 72 64 77 72 61  |e how to wordwra|
00000020  70 20 69 6e 0d 00 14 0f  f4 20 61 73 73 65 6d 62  |p in..... assemb|
00000030  6c 65 72 0d 00 1e 05 3a  0d 00 28 10 de 20 77 72  |ler....:..(.. wr|
00000040  61 70 25 20 26 31 30 30  0d 00 32 24 6f 73 6e 6c  |ap% &100..2$osnl|
00000050  3d 26 46 46 45 37 3a 6f  73 61 73 3d 26 46 46 45  |=&FFE7:osas=&FFE|
00000060  33 3a 6f 73 77 63 3d 26  46 46 45 45 0d 00 3c 4f  |3:oswc=&FFEE..<O|
00000070  61 64 64 72 4c 3d 26 37  30 3a 61 64 64 72 48 3d  |addrL=&70:addrH=|
00000080  26 37 31 3a f4 20 48 69  20 61 6e 64 20 6c 6f 77  |&71:. Hi and low|
00000090  20 62 79 74 65 73 20 6f  66 20 74 68 65 20 61 64  | bytes of the ad|
000000a0  64 72 65 73 73 20 77 68  65 72 65 20 74 68 65 20  |dress where the |
000000b0  74 65 78 74 20 73 74 61  72 74 73 0d 00 46 0e 6f  |text starts..F.o|
000000c0  6c 64 70 6f 73 3d 26 37  32 0d 00 50 05 3a 0d 00  |ldpos=&72..P.:..|
000000d0  5a 0c e3 58 3d 30 b8 33  88 33 0d 00 64 0c 50 25  |Z..X=0.3.3..d.P%|
000000e0  3d 77 72 61 70 25 0d 00  6e 09 5b 4f 50 54 58 0d  |=wrap%..n.[OPTX.|
000000f0  00 78 0e 2e 67 65 74 73  74 72 69 6e 67 0d 00 82  |.x..getstring...|
00000100  28 5c 53 74 61 72 74 20  61 74 20 74 68 65 20 65  |(\Start at the e|
00000110  6e 64 20 61 6e 64 20 77  6f 72 6b 20 62 61 63 6b  |nd and work back|
00000120  77 61 72 64 73 0d 00 8c  38 4c 44 59 23 33 39 3a  |wards...8LDY#39:|
00000130  5c 4f 66 66 73 65 74 20  33 39 20 69 73 20 74 68  |\Offset 39 is th|
00000140  65 20 65 6e 64 20 6f 66  20 74 68 65 20 34 30 20  |e end of the 40 |
00000150  63 6f 6c 75 6d 6e 20 73  63 72 65 65 6e 0d 00 96  |column screen...|
00000160  0e 2e 67 65 74 6c 65 74  74 65 72 0d 00 a0 4b 4c  |..getletter...KL|
00000170  44 41 28 61 64 64 72 4c  29 2c 59 3a 43 4d 50 23  |DA(addrL),Y:CMP#|
00000180  97 22 30 22 3a 42 43 43  77 72 61 70 70 6f 69 6e  |."0":BCCwrappoin|
00000190  74 66 6f 75 6e 64 3a 44  45 59 3a 42 4d 49 6e 6f  |tfound:DEY:BMIno|
000001a0  77 72 61 70 70 6f 69 6e  74 3a 4a 4d 50 67 65 74  |wrappoint:JMPget|
000001b0  6c 65 74 74 65 72 0d 00  aa 05 3a 0d 00 b4 13 2e  |letter....:.....|
000001c0  77 72 61 70 70 6f 69 6e  74 66 6f 75 6e 64 0d 00  |wrappointfound..|
000001d0  be 37 5c 4d 69 67 68 74  20 73 74 69 6c 6c 20 62  |.7\Might still b|
000001e0  65 20 28 6f 72 20 6d 69  67 68 74 20 62 65 29 20  |e (or might be) |
000001f0  61 20 63 61 72 72 69 61  67 65 20 72 65 74 75 72  |a carriage retur|
00000200  6e 20 74 6f 6f 0d 00 c8  17 49 4e 59 3a 53 54 59  |n too....INY:STY|
00000210  6f 6c 64 70 6f 73 3a 4c  44 59 23 30 0d 00 d2 13  |oldpos:LDY#0....|
00000220  2e 63 61 72 72 69 61 67  65 73 65 61 72 63 68 0d  |.carriagesearch.|
00000230  00 dc 46 4c 44 41 28 61  64 64 72 4c 29 2c 59 3a  |..FLDA(addrL),Y:|
00000240  43 4d 50 23 31 33 3a 42  45 51 63 61 72 72 69 61  |CMP#13:BEQcarria|
00000250  67 65 72 65 74 75 72 6e  3a 49 4e 59 3a 43 50 59  |gereturn:INY:CPY|
00000260  23 34 30 3a 42 4e 45 63  61 72 72 69 61 67 65 73  |#40:BNEcarriages|
00000270  65 61 72 63 68 0d 00 e6  1c 4c 44 41 6f 6c 64 70  |earch....LDAoldp|
00000280  6f 73 3a 4a 53 52 70 72  69 6e 74 69 74 74 68 65  |os:JSRprintitthe|
00000290  6e 0d 00 f0 36 4c 44 41  6f 6c 64 70 6f 73 3a 43  |n...6LDAoldpos:C|
000002a0  4d 50 23 34 30 3a 42 45  51 67 65 74 73 74 72 69  |MP#40:BEQgetstri|
000002b0  6e 67 3a 4a 53 52 6f 73  6e 6c 3a 4a 4d 50 67 65  |ng:JSRosnl:JMPge|
000002c0  74 73 74 72 69 6e 67 0d  00 fa 17 45 51 55 53 22  |tstring....EQUS"|
000002d0  28 43 29 31 39 39 38 20  53 50 52 4f 57 22 0d 01  |(C)1998 SPROW"..|
000002e0  04 05 3a 0d 01 0e 13 2e  63 61 72 72 69 61 67 65  |..:.....carriage|
000002f0  72 65 74 75 72 6e 0d 01  18 23 5c 50 72 69 6e 74  |return...#\Print|
00000300  20 75 70 74 6f 20 74 68  65 20 63 61 72 72 69 61  | upto the carria|
00000310  67 65 20 72 65 74 75 72  6e 0d 01 22 27 49 4e 59  |ge return.."'INY|
00000320  3a 54 59 41 3a 4a 53 52  70 72 69 6e 74 69 74 74  |:TYA:JSRprintitt|
00000330  68 65 6e 3a 4a 4d 50 67  65 74 73 74 72 69 6e 67  |hen:JMPgetstring|
00000340  0d 01 2c 05 3a 0d 01 36  10 2e 6e 6f 77 72 61 70  |..,.:..6..nowrap|
00000350  70 6f 69 6e 74 0d 01 40  33 5c 4a 75 73 74 20 70  |point..@3\Just p|
00000360  72 69 6e 74 20 6f 75 74  20 34 30 20 6c 65 74 74  |rint out 40 lett|
00000370  65 72 73 20 63 6f 73 20  77 65 20 63 6f 75 6c 64  |ers cos we could|
00000380  6e 27 74 20 77 72 61 70  0d 01 4a 26 4c 44 41 23  |n't wrap..J&LDA#|
00000390  34 30 3a 4a 53 52 70 72  69 6e 74 69 74 74 68 65  |40:JSRprintitthe|
000003a0  6e 3a 4a 4d 50 67 65 74  73 74 72 69 6e 67 0d 01  |n:JMPgetstring..|
000003b0  54 05 3a 0d 01 5e 10 2e  70 72 69 6e 74 69 74 74  |T.:..^..printitt|
000003c0  68 65 6e 0d 01 68 27 5c  50 72 69 6e 74 73 20 6f  |hen..h'\Prints o|
000003d0  75 74 20 27 6e 27 20 63  68 72 73 20 73 70 65 63  |ut 'n' chrs spec|
000003e0  69 66 69 65 64 20 69 6e  20 41 0d 01 72 11 4c 44  |ified in A..r.LD|
000003f0  59 23 30 3a 54 41 58 3a  44 45 58 0d 01 7c 0e 2e  |Y#0:TAX:DEX..|..|
00000400  70 72 69 6e 74 6c 6f 6f  70 0d 01 86 3d 4c 44 41  |printloop...=LDA|
00000410  28 61 64 64 72 4c 29 2c  59 3a 42 45 51 70 72 69  |(addrL),Y:BEQpri|
00000420  6e 74 6a 6f 62 64 6f 6e  65 3a 4a 53 52 6f 73 77  |ntjobdone:JSRosw|
00000430  63 3a 49 4e 59 3a 44 45  58 3a 42 50 4c 70 72 69  |c:INY:DEX:BPLpri|
00000440  6e 74 6c 6f 6f 70 0d 01  90 0d 2e 70 72 69 6e 74  |ntloop.....print|
00000450  61 64 64 0d 01 9a 1d 54  59 41 3a 43 4c 43 3a 41  |add....TYA:CLC:A|
00000460  44 43 61 64 64 72 4c 3a  53 54 41 61 64 64 72 4c  |DCaddrL:STAaddrL|
00000470  0d 01 a4 46 4c 44 41 23  30 3a 41 44 43 61 64 64  |...FLDA#0:ADCadd|
00000480  72 48 3a 53 54 41 61 64  64 72 48 3a 52 54 53 3a  |rH:STAaddrH:RTS:|
00000490  5c 42 75 6d 70 20 75 70  20 74 68 65 20 61 64 64  |\Bump up the add|
000004a0  72 65 73 73 20 62 79 20  27 6e 27 20 63 68 61 72  |ress by 'n' char|
000004b0  61 63 74 65 72 73 0d 01  ae 11 2e 70 72 69 6e 74  |acters.....print|
000004c0  6a 6f 62 64 6f 6e 65 0d  01 b8 32 50 4c 41 3a 50  |jobdone...2PLA:P|
000004d0  4c 41 3a 52 54 53 3a 5c  53 75 63 6b 20 6f 66 66  |LA:RTS:\Suck off|
000004e0  20 74 6f 70 20 73 74 61  63 6b 20 65 6e 74 72 79  | top stack entry|
000004f0  20 61 6e 64 20 71 75 69  74 0d 01 c2 05 5d 0d 01  | and quit....]..|
00000500  cc 05 ed 0d 01 d6 0f de  74 65 78 74 25 20 35 30  |........text% 50|
00000510  30 30 0d 01 e0 27 3f 61  64 64 72 4c 3d 74 65 78  |00...'?addrL=tex|
00000520  74 25 20 83 32 35 36 3a  3f 61 64 64 72 48 3d 74  |t% .256:?addrH=t|
00000530  65 78 74 25 20 81 32 35  36 0d 01 ea 09 db 3a ef  |ext% .256.....:.|
00000540  31 34 0d 01 f4 1b ff 22  4c 4f 41 44 20 54 65 73  |14....."LOAD Tes|
00000550  74 65 72 20 22 2b c3 7e  74 65 78 74 25 0d 01 fe  |ter "+.~text%...|
00000560  0a d6 77 72 61 70 25 0d  ff                       |..wrap%..|
00000569