GPS PPS Sync
This project is a small utility project for synchronizing a personal computer (PS) with a GPS receiver with a pulse per second output.
license allows non-restrictive use for commercial and open source development.
*The PPS signal is a TTL signal and not at RS232 voltage levels. This method has worked without a signal converter but if you so desire you can use a TLL to RS232 signal converter (~$50) before connecting to pin 9 of the PC serial port.
In this example, the I/O port cable and the RS232 serial communications cable, RX COM1, are combined using a connector box. The PPS pin, pin 2 of the OEM3 GPS receiver's I/O cable, is connected to pin 9 of the RS232 communcations cable. The ground pins of the I/O cable should be connected appropriately in the connector box as well. A null modem cable is connected to the connector box and the user's PC. For details about OEM3 pin output refer to http://www.novatel.com/Documents/Manuals/om-20000016.pdf.
- Modify the serial cable connecting the GPS receiver to the PC serial port by:
- Connect the PPS output of the receiver to pin 9, ring indicator (RI) pin, of the PC serial port.*
- Connect the ground pins of the input/output (I/O) connects to the ground pin, pin 5, on the PC serial port.