Most BASICS, however, are not quite that straightforward. For exarrmle. the
IBM-PC will give you a printout similar to Fi-gure 2-6. I
,:ir, <Cl! t-1.: 3-r 8’1*+ c-1” \fS 1/T \‘18 *-<ii <Ifi t-IF< <Ii- CilJ <-,a t.,F . . . . . . . ..“......
I:,F !CC i ! !r‘ 17 14 15 i,& 17 Iii j’: 1P lr 1D 1E IF ..“.............
;a‘, r‘, 2” :--: L“? -r -i ;‘;,’
_. 1 SC-’ -3 -7 y,:, =p ,i‘ TD YE ?F ‘“#$%&‘()L+,-.,
71’1 II T’ 7- ;4 y’ 75 T7
._1_1 IL’ -:a ‘Y-7 ‘Xrri ::p :r l.D YE -;:F r:,, >Sq.567E(Q : : = 3
4,-’ 41 4:’ 4:, 44 45 4A 4-7 48 44 40 4B 4C 4D 4E 4F WBCDEFGHI Jt LMhlO
?.,,:I 5, 5: 53 54 55 56 57 5R 59 :?A 58 Xc: 5D SE ‘;F ~QwY-uvwxYzI: \ 1 _
hll 51 62 h 54 65 66 67 68 h9 6k hR hC 6D 6F hF Tabcdefghl ji: lmno
70 71 72 75 74 75 76 77 7s -?y 70 78 7C 7D -IL! 7F pqr-iituvw:-:y~:: 3”
RO 81 nz ~3 e4 85 i3h 87 BR 89 SA eH RC flD 8E SF . . . . . . . . . . . . . . . .
9,:) 91 92 93 94 95 96 97 98 YQ 9A 9H YC 9D 9E YF . . . . . . . . . . . . . . . .
a0 Al a,’ A? A4 as Ah 67 AR A9 clA AR AC AD AE !AF .“,.............
PO Hl H2 HZ S4 B5 Rb 87 Hi3 B9 HA HH PC HD SE SF . . . . . . . . . . . . . . . .
co Cl c2 c1: c4 c5 Cb c7 C8 C9 CA CH CC CD CE CF . . . . . . . . . . . . . . . .
DO Di D2 D9 D4 D5 D6 D7 DS D9 DA DB DC DD DE DF . ..*........
Ei:) El E2 E; E4 E5 Eb E7 ES E9 EFI ER EC ED EE EF ::::....
FO Fl F? F3 F4 F-5 F6 F7 FS F9 FFI FR FC FD FE FF . . . . . . . . . . . . . . . .
c-j,, I-IA . .
@re 2-6. Sample hexadecimal dump with IBM-PC
When the IBM-PC BASIC interpreter sends hex code OD (carriage return)
it adds an extra hex OA (line feed). Hex code 1A (end-of-file) also gets
special treatment: the interpreter does not send it at all. This can cause
problems with graphics or download character data. However, you can solve
this problem by changing line 20 in the preceding program and adding the
coding shown below.
Coding for IBM-PC with monochrome display:
20 GOSUB 100
100 X=INP(&H3BD) :IF X(128 THEN 100
110 OUT &H3BC,I :OUT &H3BE,5 :OUT 6tH3BE.4
120 RETURN
Coding for IBM-PC with color adapter:
20 GOSUB 100
100 X=INP(&H379) -IF X(128 THEN 100
110 OUT bH378,I :&JT &H37A,5 :OUT &H37A,4
120 RETURN
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