GPSPCI USER MANUAL www.masterclock.com 2484 W Clay St, St. Charles MO 63301 GPSPCI 2/7/2008 Rev 1.2.1 Tel: 636-724-3666 Fax: 636-724-3776 © Masterclock, Inc. Jan-10 Printed in USA a Masterclock, Inc.
TABLE OF CONTENTS DISCLAIMER ......................................................................................................................................... c ADVISORY NOTICE ................................................................................................................... c INTRODUCTION ................................................................................................................................... 1 GPS Satellites ...............................................
DISCLAIMER The information contained in this document is subject to change without notice. Masterclock®, Inc. (hereinafter Masterclock) makes no warranty of any kind with regard to this material, including, but not limited to, the implied warranties of merchantability and fitness for a particular purpose. Masterclock shall not be liable for errors contained herein or for incidental or consequential damages in connection with the furnishing, performance, or use of this material.
INTRODUCTION The GPSPCI is a PCI card that provides very stable accurate time and date information for a Windows PC. The card receives reference time information from Atomic Clocks in the GPS (Global Positioning System) satellites. GPS SATELLITES The GPS satellites are operated and maintained by the US Department of Defense and allow for the precise determination of local time and location at any point on (or above) the Earth.
The GPSPCI’s GPS navigation module has its own backup battery that maintains startup data when the PC is powered down. If, when starting up, the location, time and number of satellites that the GPSPCI can receive has not changed significantly since last power down, then the GPSPCI time will be available much faster.
During such outages the GPSPCI will continue to generate time information referenced to the last available satellite timing information. This mode is referred to as freewheeling. When the unit first acquires satellite time, it calibrates an internal clock against the incoming atomic time. During freewheeling the time information will be referenced to this clock and will typically be accurate to within a few milliseconds over a 24 hour period (if the power is not disconnected).
Software application developers, may refer to the MCRPC-GPS ISA/PCI Bus Interface Protocol Version 1.1.0 which is available for download from the support area of our website. http://www.masterclock.com/data_files/mcrpc-gps-card-protocolV110.pdf DB-9 CONNECTIONS Pin 1 - Pulse Out TTL-level 100ms active low pulse generated once per second by the GPS receiver. The negative-going edge of the pulse is aligned with UTC (Greenwich Mean Time) when the receiver has a 3-dimensional GPS satellite fix.
• This function allows external devices connected via the DB9 connector to operate in a listen only mode to broadcast NMEA messages from the GPS receiver. • This monitor function is always enabled at 9600 Baud (Note: most GPS receivers support a native baud rate of 4800). • Monitoring may be done using a simple terminal monitor application such as Windows Hyperterminal or by writing a custom serial port monitoring application. See Hyperterminal sample below.
PRE-AMPLIFIED ANTENNA The GPSPCI requires a pre-amplified antenna. It provides 5 VDC via the center pin of the coaxial for remote power. Warning: Attaching a passive (non pre-amplified) antenna to the GPSPCI could destroy the GPS receiver module. This is a major repair cost, which is not covered by warranty. The unit is tested and shipped with the appropriate cable for the antenna that was ordered.
PC BOARD LAYOUT Rechargeable Battery GPS receiver module GPS Lock Status Indicator GPS antenna connector (SMA female) DB9 Connector Pin 1 – PPS, TTL Pin 3 – NMEA out, RS232 Pin 5 – Ref/Gnd GPSPCI V1.2 GPSPCI 2/72008 Rev 1.2.1 7 Masterclock, Inc.
SPECIFICATIONS TIMING CHARACTERISTICS Reference: ........................UTC/GMT (default) Date Short term accuracy .........± 10 µs Long term stability ...........same as GPS atomic clock POWER SUPPLY REQUIREMENTS Contains its own CPU and requires only DC power from the PC PHYSICAL GPSPCI-PCI ....................1/3 slot AT/PCI card, +5VDC OPERATING TEMPERATURE Temperature .....................0 to +70 °C PRE-AMPLIFIED ANTENNA Frequency.........................1575 MHz ± 10 MHz Polarization ...............
LIMITED WARRANTY This Masterclock Inc. (hereinafter Masterclock) product warranty extends to the original purchaser. Masterclock warrants the GPSPCI against defects in materials and workmanship for a period of five years from date of sale. If Masterclock receives notice of such defects during the warranty period, Masterclock will, at its option, either repair or replace products that prove to be defective.
