Comtech EF Data SNM-1001 - Manual (Page 41)

Theory of Operation SNM-1001 Network Control Modem
4–10 Rev. 1
4.3.2 Remote Interface Specification
Refer to Appendix A for the remote interface specification.
4.3.3 M&C Theory of Operation
The M&C module is built around the Intel 80C32 micro-controller, operating at
11.0592 MHz. The microsystem is designed to support up to 512 kbytes of read-only
code memory, and up to 32 kbytes of non-volatile random-access data memory.
4.3.4 Remote Interface Configuration
All modem functions can be remotely controlled and monitored via an EIA-232-C
communications link. The EIA-232-C interface is used to communicate with a single
modem.
For M&C jumper settings, refer to Table 4-1.
4.3.5 Modem Defaults
The M&C has default settings that are loaded into the modem at power-up. These default
settings are also loaded each time the modem has been hard reset. The following tables
list the defaults settings for each modem configuration parameter.
Defaults for Burst Mode
Modulator Defaults Demodulator Defaults
Data Rate A Data Rate A
TX Rate A 19.2 kbit/s, QPSK RX Rate A 19.2 kbit/s, QPSK
TX-IF Frequency 70 MHz RX-IF Frequency 70 MHz
TX-IF Output ON Descrambler ON
Mod Power Offset 0 dB Differential Decoder OFF
TX Power Output -10 dBm Demodulator Type INTELSAT Open
Scrambler ON Decoder Type Viterbi, 1/2 Rate
Differential Encoder OFF IF Loopback OFF
Modulator Type INTELSAT Open RF Loopback OFF
Encoder Type Viterbi, 1/2 Rate BER Threshold None
CW Mode Normal (OFF)
Interface Defaults System Defaults
TX Clock Source TX TERRESTRIAL Time 12:00 AM
TX Clock Phase NORMAL Date 7/4/76
RX Clock Phase NORMAL Baud Rate 9600
Baseband Loopback OFF Parity Even
Address 1
Operation Mode Duplex