If your system passes the codes directly to the printer without changing
them, you will get a printout like Figure 2-3.
00 01 02 03 04 05 06 07 08 09 OA 06 OC OD OE OF
10 11 12 13 14 15 16 17 18 19 1A 18 1C 1D 1E 1F
20 21 22 23 24 25 26 27 28 29 2A 28 ZC 2D 2E ZF
30 31 32 33 34 35 36 37 38 39 3A 38 3C 3D 3E 3F
ii 41 42 43 44 45 46 47 48 49 4A 48 4C 40 4E 4F
50 51 52 53 54 55 56 57 58 59 5A 58 5C 50 5E 5F
60 61 62 63 64 65 66 67 68 69 6A 6R 6C 6D 6E 6F
70 71 72 73 74 75 76 77 78 79 7A 78 7C 7D 7E 7F
80 81 82 83 84 85 86 87 88 89 8A 88 8C 8D 8E 8F
90 91 92 93 94 95 96 97 98 99 9A 98 9C 9D 9E 9F
A0 Al A2 A3 A4 A5 A6 A7 A8 A9 AA AB AC AD AE AF
80 81 62 83 84 R5 66 87 88 69 BA RB 8C BD BE BF
CO Cl C2 C3 C4 C5 C6 C7 C8 C9 CA CB CC CD CE CF
DO 01 02 D3 04 D5 D6 D7 08 D9 DA DB DC DD DE DF
ii 21 E2 E3 E4 E5 E6 E7 E8 E9 EA EB EC ED EE EF
FO Fl F2 F3 F4 F5 F6 F7 FB F9 FA FB FC FD FE FF
00 OA
__......
.i-#iXi: ij*+,-.,
01234567 89:;<=>?
@ABCDEFG HIJKLMNO
PQRSTUVW XYZ[\l--
‘abcdefg hijklmno
pqrstuvw xyz{l)~0
. . . . .
. . . . . .
. . .
. . .
.
..,..... . . . .
. . . . .
..,.....
.
Most BASICS, however, are not quite that straightforward. For example,
the IBM-PC prints the following.
00 01 02 03 04 05 06 07 08 09 OA 08 OC OD OA OE
OF 10 11 12 13 14 15 16 17 18 19 18 1C 1D 1E 1F :::::::I ::::::..
20 21 22 23 24 25 26 27 28 29 2A 28 2C 2D 2E 2F !“#$%&’ ox+.-./
30 31 32 33 34 35 36 37 38 39 3A 38 3C 30 3E 3F 01234567 89:;<=>?
40 41 42 43 44 45 46 47 48 49 4A 48 4C 4D 4E 4F @ABCDEFG HIJKLMNO
50 51 52 53 54 55 56 57 58 59 5A 58 SC 5D 5E 5F PQRSTUVW XYZ [\I -_
60 61 62 63 64 65 66 67 68 69 6A 68 6C 6D 6E 6F ‘abcdefg hijklmno
70 71 72 73 74 75 76 77 78 79 7A 78 7C 7D 7E 7F pqrstuvw xyz{l)-o
80 81 82 83 84 85 86 87 88 89 8A 88 8C 8D 8E 8F ____,.._ __._....
90 91 92 93 94 95 96 97 98 99 9A 98 9C 9D 9E 9F _....... . . . . . . . .
A0 Al A2 A3 A4 A5 A6 A7 A8 A9 AA AB AC AD AE AF
50 81 B2 83 84 55 86 87 B8 B9 BA BB BC 8D BE BF :::::::: :::I::..
CO Cl C2 C3 C4 C5 C6 C7 C8 C9 CA CB CC CD CE CF .,...... . . . . . . . .
DO Dl D2 D3 D4 D5 D6 D7 08 09 DA 08 DC DD DE DF
EO El E2 E3 E4 E5 E6 E7 E8 E9 EA EB EC ED EE EF :::::::: ::::::::
FO Fl F2 F3 F4 F5 F6 F7 F8 F9 FA FB FC FD FE FF . .
OD OA
Figure 2-4. Sample hexadecimal dump with IBM-PC
When the IBM-PC BASIC interpreter sends hex code OD (carriage re- -- turn) it adds an extra hex OA (line feed). Hex code IA (end-of-file) also gets -
special treatment: the interpreter does not send it at all. This can cause
problems in programs that generate graphics or download character data, -
but there is a solution. Try changing line 20 in the preceding program and
adding the coding shown below.
Coding for IBM-PC with monochrome display:
20 GOSUB 100
100 O=INP(&H3BD) :IF 0<128 THEN 100
110 OUT &H3BC,I :OUT &H3BE,5 :OUT &H3BE,4
120 RETURN
24