CG2-SHANTY • CompactPCI GPS Receiver/Clock
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EKF Elektronik GmbH • Philipp-Reis-Str. 4 • 59065 HAMM • Germany
Tel. +49 (0)2381/6890-0 • Fax. +49 (0)2381/6890-90 • E-Mail [email protected] • Internet www.ekf.com
JBAT
removed
set
data retention mode
battery not connected
Serial Ports & Protocols
The Jupiter module communicates with the host across its primary serial port. The bit rate is
fixed to 4800bps, no parity, 8 data bits, 1 stop bit. Commands are passed to the module, which
responds accordingly with results and status information. Due to the low data transfer rates,
there is no hardwired handshake available.
There are two choices for protocol selection. By default, the NMEA standard is selected on the
Jupiter Module. This is an ASCII based protocol, widely accepted as a common base to all GPS
application programs. As an alternate, the Jupiter module can be configured to communicate
by a proprietary, binary protocol (SiRF binary messages). On writing own firmware, the binary
protocol could be a more efficient solution. The binary protocol also allows for defining higher
bit rates on both serial interfaces. Please contact EKF when you need the binary protocol feature.
The secondary (auxiliary) serial port of the Jupiter module is configured as a half duplex input at
9600bps, no parity, 8 data bits, one stop bit. This interface is configured to receive RTCM DGPS
correction data messages. Usage of this port is optional.
There are four indicator LEDs mounted in the front panel to signal both RXD and TXD of the
primary serial interface, and RXD only of the auxiliary serial interface.
Auxiliary Power
The CG2-SHANTY is equipped with a Lithium cell battery. Close the jumper JBAT to provide this
auxiliary power to the Jupiter receiver module (you have to set this jumper for any new board,
because the factory default is off for saving cell lifetime while storing). Data retention for the
GPS receivers SRAM and RTC is nominal 4750hrs. Loss of SRAM or RTC data results in slower
response time (TTFF) after powering up the CG2-SHANTY, but the GPS receiver remains fully
operable. For replacement of the battery, observe precautions and follow the procedure
described in chapter ‘Replacement of the Battery’.
