Radio Shack TRS-80 Model 100 Basic Manual page 152

As you can see, the first number in the SOUND statement controls the frequency of
the tone and is inversely related to the frequency (the higher the number, the lower the
tone).
Increase the duration of the 440 hertz tone by entering:
SOUND 5588, 255
and decrease the duration by entering:
SOUND 5588,1
The length of the tone is controlled by the second number in the SOUND statement
and ranges from a minimum of 0 (no sound at all) to a maximum of 255. The duration
of the tone is approximately 20 milliseconds times the number entered. For example,
the command
SOUND 5586,1121121
turns on a 440 hertz tone for approximately
20
*
100
=
2000 milliseconds
=
2 seconds
The first number in the SOUND statement determines the frequency of the tone and
must be an integer in the range of 0 to 16383. You can hear the full range of tones by
entering the following program:
1121 FOR I
=
121 TO 18383 STEP 1121121
20 SOUND 1,2
30 NEXT I
Execute the program.
The sounds you hear are tones of approximately 40 milliseconds duration, ranging
from the highest frequency (0) to the lowest frequency (16383) in increments of 100.
The frequency specifier is related to the musical scale, as seen in the table below:
Note 1
C
C#
D
D# 15800
E 14912
F 14064
F# 13284
G 12538
G# 11836
A 11172
A# 10544
B 9952
OCTAVE
2
3
4 5 6
9394 4697 2348 1171 587
8866 4433 2216 1103 554
8368
4184
2092
1045 523
7900 3950 1975 987 493
7457 3728 1864 932 466
7032 3516 1758 873 439
6642 3321 1660 830 415
6269 3134 1567 783
5918
2954 1479 739
5586 2793 1396 693
5272
2636 1318 659
4968 2484 1244 622
146