Radio Shack TRS-80 Model 100 Basic Manual page 123

Experiment #7 Displaying ASCII Characters
Type the following program:
10 FOR I
=
65 TO 90
20 PRINT CHR$( I) ;
30 NEXT I
and execute the program. You will see the alphabet displayed:
ABCDEFGHIJKLMNOPQRSTUVWXYZ
Ok
•
Character
Returned
Argument
Value
This program defines a loop which displays the CHR$ function with values for the
argument ranging from 65 to 90. The character returned by the CHR$ function for
these arguments is illustrated in the table below:
Argument Character
Value Returned
65 A 78 N
66
B 79 0
67 C
80 P
68
0
81 Q
69 E 82 R
70
F
83 S
71 G 84
T
72
H 85
U
73
I 86
V
74 J
87
W
75
K 88
X
76 L
89
Y
77
M 90 Z
The number assigned to each letter in the table above is called its ASCII value. The
range of possible ASCII values is 0 to 255 and includes all characters which your
computer can store in its memory.
In addition to the upper case alphabet, there are ASCII values assigned to the lower
case alphabet as well. These can be printed by changing line 10 in your program to:
10 FOR I = 97 TO 122
~
117