Motorola ACE3600 RTU, Owner'S Manual

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Audio Control and Tone (ACT) Module
23-4
Audio Handling Capabilities
The ACT module has built-in hardware which records and stores audio signals by digitizing
the signal from an audio source connected directly to the module’s low-level audio input. The
module can play these pre-recorded audio signals once or repeatedly.
To facilitate the recording process, audio signals may be formed or saved in "WAV" file
format on a PC (or on any other audio format provided it can be played by a PC) and then
downloaded to the module through the PC audio out.
The module’s total recording capacity is 240 seconds. As default, the recording space is
divided into eight "cells” (each of which holds up to 30 seconds). The number of cells is
configurable and can be set to 1, 2, 4, 8, 16, 30 and 60.
NOTE: Recording will automatically terminate 2 seconds after the module detects silence.
Recording will also be stopped when the "cell" has run out of recording capacity.
The module’s low-level audio input also enables the connection of an external low-level audio
source (such as a radio audio output) for direct routing to an audio amplifier. Thus the audio
routed to this output can be either a pre-recorded audio signal or an external source, connected
to the low-level audio input.
Two high-level audio inputs are used to route amplified audio signals into the module. The
ACT module has six high-level audio outputs that can be routed to selected speakers.
Interface to the RTU
The ACT module interfaces to the RTU via an RS232 port, marked as COM IN. The
communication with the RTU is based on an 8-bit code protocol.
The ACT module also enables the RTU to have more than one use for its RS232 port. The
application on board the RTU may select its serial port connected to COM IN to control the
ACT module or to send data to COM OUT. This is very useful for connecting a dot matrix
printer to the RTU without requiring an additional serial port which could necessitate the
another CPU.
The destination of the serial data sent to the COM IN port is selected via the following
mechanism:
•
Set DTR signal "Off" – Data is routed to COM OUT.
•
Set DTR signal "On" – Data protocol controlling the ACT.
The ACT module operates on 9 to 16 VDC, usually supplied by the RTU's auxiliary power
supply.
An RTU application program controls the ACT module via a user port using an 8-bit
instruction set.
The ACT module returns simple 8-bit codes as a response to instructions.