Guardian G25AMK005, Техническое руководство

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3-12 G U A R D I A N V H F 1 1 0 W M O B I L E
Keypad power up okay
Keypad error 1-n
Key press 1-16
Key release 1-16
PTT press
PTT release
Volume switch 1-16
Channel switch 1-16
Toggle switch 1-3
Auxiliary key press 1-3
Emergency key press
•
Controller to keypad
•
Request current switch status
•
Reset and execute BIT test
•
Backlight off/bright/dim
•
LED off/red/green/yellow/flash/flash rate
•
Key press request and interrupt acknowledge
LCD data transfers are in blocks of 80 bytes maximum, allowing a pause on the serial interface at least every 100 ms
for the keypad MPU to assert the interrupt and transfer key press or switch change data. During the LCD data
transfers, the key data are buffered into the keypad MPU.
3.5 Data Interface
The DSP incorporates a user data interface through its SCI port.
3.5.1 CAI Data Interface
The DSP supports an asynchronous data interface for CAI modes using its SCI port. This interface conforms to the
CAI data peripheral interface. It uses standard V24, and RS232 baud rates up to 9600 baud. The software also
controls the associated flow control signal data of the terminal ready (DTR) input to the DSP, and the clear to send
(CTS) output from the DSP. The request to send (RTS) input to the radio for this interface is processed by H8.
3.5.2 Synchronous Serial Data Interface
The DSP supports a 12 kbps synchronous serial port using its SCI port. The interface is half duplex, uses a DSP
generated clock, and includes minimum data buffering within the DSP and RTS/CTS flow control on the transmit
function.
3.5.2.1 Receiver Synchronous Serial Data Buffering
In receive synchronous serial data modes the DSP software uses a variable length first-in first-out (FIFO) buffer to
cope with differences in clock rates between the transmitter and receiver.
3.5.3 CAI Data Link Layer
This software provides the link between the raw voice and data bit streams, in addition to the data formats required
to implement a 9.6 kbps CAI compatible interface.
3.5.3.1 CAI Transmit Voice Mode
The DSP software takes the 144 bit voice code words (encrypted or not) and a number of link control fields set by
the host H8 or from the DES system, and formats CAI-compatible logic link data units.
3.5.3.2 CAI Transmit Voice Test Modes
The DSP software is capable of transmitting the CAI voice silence test pattern, the CAI 1 kHz test pattern and a
9 x 144-bit (1296) PRBS test pattern used for error rate tests. The H8 controller controls these test modes.