Remote Processing RPC-2350 - Manual (Page 54)

CHAPTER 11 SOUND/TIMER OUTPUT
11-1
Figure 11-1 Sound/pulse output connector
Figure 10-2 Speaker interface
CHAPTER SYNOPSIS
Ž Uses and limitations of sound/timer output
Ž Connecting to a speaker
DESCRIPTION
SOUN D/T IMER OUTP UT CH APTE R 11
Sound may be used to drive a speaker or generate square
wave pulses.
Sound timer an d output line is used for other pur poses.
Do NO T use SOUN D when using any of the following:
RS-485 communication
512K RAM memor y(installed)
512K Flash memory
RS-485 uses the same timer as sound. C PU addr ess line
A18 is used to address RAM and F lash or provide the
p u ls e ou tp u t f o r S O U N D .
SOUN D Syntax is:
S O U N D frequency
frequency is from about 15 Hz to over 20,000 Hz.
Output is ava ilable only dur ing run tim e. It is sh ut off in
the immediate mode (i.e. Entering code.)
Frequency accuracy is dependent upon the CPU crystal
of 18.432 MHZ . The factor that determines frequency
accuracy and resolution is the basic timer frequency of
921.6 kHz. The timer is a 16 bit, meaning that there are
6 5 , 5 36 p os si bl e f r e qu e nc i es w it hi n t he 9 21 . 6 K H z
window. What this means is that while you might
request a frequency, say 10,000 Hz, you will get
something else. This is especially true at higher
frequencies.
Sound output is available from J10-3. This output can
go to a speaker or the counter at J10.
CONNECTING TO A SPEAKER
Refer to figure 11-2 below for circuit connections to a
speaker. T he series resistor determines the volume. the
Capacitor sets the lower frequency limit. Generally,
values from 100 uF to 470 uF ar e adequate. The
speaker may be any value but those with 50 ohms or
greater produc e higher d b output.