EndRun Sonoma N12, User Manual

Page: 111 / 174

S o n o m a U s e r M a n u a l 94
C H A P T E R T E N
95 S o n o m a U s e r M a n u a l
O P T I O N S
Alarm Output
The Alarm Output provides an open-collector output that indicates when the GPS Subsystem has lost
lock, or when serious hardware faults are detected. For a detailed description of the faults see Appen-
dix G - System Faults.
Care should be taken not to directly connect this open-collector output to a voltage source. A series
current-limiting resistor of at least 1K ohms in value should be used. The pull-up voltage must not
exceed 40V. The Alarm Output connector can be either a BNC or a terminal block. For more details
see Appendix H - Specifications .
View the Alarm Output Connector
Use the
cpuio
command to view the optional outputs on the CPU Module. This command will list
any connector that has an optional I/O signal. Connectors are identified as A, B or C.
Command:
cpuio
Sonoma reply:
CPU I/O C - OPEN COLLECTOR ALARM OUTPUT is Installed
Direct Digital Synthesizer (DDS)
The DDS Option provides user-selectable pulse rates from 1 Hz to 10 MHz, programmable in 1 PPS
steps, including 1.544 MPPS or 2.048 MPPS. The selected pulse rate is phase locked to the system oscil-
lator and is not aligned with system time.
The DDS is a “system signal”. This means that there is one DDS signal that affects the whole system.
In other words, if your Sonoma has multiple DDS outputs and you change the pulse rate, then all DDS
outputs will be affected.
The pulse rate is 0 Hz when shipped from the factory but can be changed (see below). For details on
the DDS signal definition see
Appendix H - Specifications
.
View and Change the DDS Configuration
Use the
cpuio
command to view the optional outputs on the CPU Module. This command will list
any connector that has an optional I/O signal. Connectors are identified as A, B or C. Use the
syste-
mio
command to view the DDS rate.
Command:
cpuio
Sonoma reply:
CPU I/O C - DIRECT DIGITAL SYNTHESIZER OUTPUT is Installed
Current Setting = (See systemio command)
Command:
systemio
Sonoma reply:
System I/O Signal DIRECT DIGITAL SYNTHESIZER OUTPUT Installed
Current Setting = 0 Hz
Use the
systemioconfig
command to change the DDS rate.
Command:
systemioconfig
Sonoma reply: Interactive script is started so you can change the DDS rate.