| Q. |
How do I know if the module is operating correctly? |
| A. |
A GPS fix within 120 seconds will show the unit is receiving a reasonable signal and is working. Using the Labmon Analyser PC software and a comport serial adapter, the signal levels of each satellite can be measured. Satellite signal levels should be in the range 35 to 48 dBHz. |
| Q. |
What supply Voltage must be used? |
| A. |
The Jupiter 12 operates from 3.3 to 5 VDC. |
| Q. |
How long does the unit take to get a GPS fix? |
| A. |
The unit will normally get a GPS fix within 120 seconds from a cold start. |
| Q. |
What is the format of the output data? |
| A. |
The Jupiter 12 default data protocol is Navman binary at 9600 baud. NMEA (a standard protocol for marine electronics) is also available. Most GPS software applications use NMEA as their input. |
| Q. |
Is the main serial port used exclusively for serial data I/O? |
| A. |
Yes, the auxiliary port is used for DGPS data input. |
| Q. |
Why does the unit get good signal levels, but does not get position fix? |
| A. |
This can be caused by too much electrical noise in the customer application. Try moving the antenna away from noise sources, or try more filtering on the Jupiter 12 power supply. |
| Q. |
Why does the unit not output any data? |
| A. |
- Check the level on PWRIN pin 2. This should be at least 3.3 VDC (main supply present).
- Check the supply current which starts low (~ 20 mA) then rises to ~ 85 mA about 2 seconds after power on (processor is running).
- Check 1PPS output is pulsing once per second (processor is running).
- Check the reset input level on pin 5. This should be PWRIN voltage (master reset is inactive)
- Check the presence of serial data on pin 11 |