Self Test - JRC FF50 Service Manual

10. SELF TEST

The FF50 has a built-in self test function with which you can check the operating status of
the FF50 automatically. Moreover, a function of monitoring input NMEA0183 formatted
sentences is attached to the self test function, and you can easily check various data input
from external equipment.
The self test function has the following four functions.
Internal checking function:
Checks DPU and shows OK or NG as the result.
Input data monitoring function:
Displays various input data including GPS/DGPS sensor and
NMEA0183 sentences on the screen.
Panel checking function:
Displays the status of the panel key that has been pushed.
Display checking function:
Displays test patterns such as crosshatch or color pattern.
When you push BRT/PWR to turn the power on while
pushing AUTO and FREQ at the same time, the FF50
enters the SELFTEST mode and the SELFTEST display
appears.
Then ROM and RAM are checked automatically and
various data as well as the
result (OK or NG) appear.
Push any panel key to change the corresponding
indicator from red to blue on the screen. When all
indicators change to blue, the panel check is completed.
After the panel check is completed, push CLR/OFF to
pause the input data display temporarily.
Push CLR/OFF again to resume the display.
When you want to check the NMEA0183 input
sentences, stop the display with this procedure to make
checking easier.
Push MENU to switch the display to test pattern. Each
time you push MENU, the
test pattern changes as long as the power is on.
Turn the power off to end the self test.
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