Audio Signaling Processor
8
MX803A PRELIMINARY INFORMATION
1996 MX
COM, INC.
Tele: 800 638 5577 910 744 5050 Fax: 910 744 5054
Doc. # 20480122.003
4.2.3 MX805A Sub-Audio Signaling Processor
This provides a sub-audio and digital signaling (NRZ) ability to LMR and other Radio Systems.
4.2.4 MX806A Audio Processor
This is a half duplex audio processor providing all DBS800 system audio signal conditioning and filtering capabilities for
the system transmit and receive paths.
4.2.5 MX809 MSK Modem
This is an intelligent, half-duplex 1200bps MSK/FFSK Modem with software programmable byte-synchronization system
and checksum generation and checking.
4.2.6 MX812 VSR Codec
This is a half-duplex CVSD speech encoder/decoder with the ability to store and retrieve data within attached DRAM
(Dynamic Random Access Memory) using an on-chip DRAM controller
4.3 C-BUS Control
C-BUS is the controlling hardware and software interface for all members of the DBS800 family. It enables the serial, bi-
directional transfer of commands and data throughout the system, allowing total flexibility of operational control and data
handling. System upgrades can be achieved by a simple software or firmware change.
The C-BUS physically consist of 5 lines. These lines are Serial Clock, Command Data, Reply Data, Chip Select ( CS),
and Interrupt Request (
IRQ
). A description of each may be found in section 2.
5. Application
Control of the MX803A Audio Signaling Processor's operation is by communication between the
μ
C and the MX803A
internal registers on the C-BUS using Address/Commands (A/Cs) and appended instructions or data. See Figure 8. The
use and content of these instructions is detailed in the following sections.
For additional application information contact MX
COM, Inc.
5.1 MX803A Internal Registers
Control Register
Status Register
RX Tone Frequency Register
RX Notone Timer
TX Tone Generator 1 Register
TX Tone Generator 2 Register
General Purpose Timer Register
30
H
31
H
32
H
33
H
34
H
35
H
36
H
Write only, control and configuration of the MX803A.
Read only, reporting of device functions.
Read only, indicates frequency of the last received input.
Write only, setting of the RX Notone period.
Write only, setting the required output frequency from TX Tone Generator 1.
Write only, setting the required output frequency from TX Tone Generator 2.
Write only, setting of a general purpose sequential time period.