Specifications

16
Two-Tone Squelch(SQ) System
The radios will support Motorola-Format, Two-Tone(Type 99) decoding. This is receive only,
decode only feature. It will allow a dispatcher to call individuals and groups. Each
System/Group will be programmable to respond to any combination of the code, with a
distinctive alert for each System/Group. The alert format consists of two tone sequences, first
the ID of the radio being called, then the ID of the calling radio.
This feature is programmed by the dealer(per customer’s request) and is not activated /
deactivated by the user. The user interface consists of the radio emitting the tones being
broadcast. At this point, the radio will enter Unmuted Rx mode and remain in this mode until the
PTT signal is inputted.
Serial command
To give the simplest protocol for control of radio, Maxon has prepared for some serial
commands which have an ease to encode and decode format. SD-160 can be used without
serial commands, but user can use its various functions through application of those, for
instance, setting-up the basic radio operation such as channel change, switch of RX/TX and
channel scan, moreover, used for control of GPS and modem option board. All messages are in
binary format, which reduces required data size to shorten response time of radio and follows
below data format.
Serial RX/TX Data Format
(1) Asynchronous Serial Data Transfer
(2) Baud Rate : 4,800 bit/sec
(3) Data Bit : 8bit , Non Parity
(4) Stop Bit : 1bit
(5) MSB first transmission
Each serial command is consist of 3 bytes. 1
st
byte is command and 2
nd
is data required by
command and 3
rd
is check sum to decide validity of total contents.
Byte0
ST 1
st
Byte (Command) SP
Byte1
ST 2
nd
Byte (Data) SP
Byte2
ST 3
rd
Byte (Check Sum) SP