Tyco Electronics A1029, Руководство пользователя

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GPS Receivers A1029
V3.2 - 02/06 User’s Manual Page 37 of 43
Figure 19: 1PPS signal description
Signal delay d (typical) 130ns
Standard deviation σ
d
(typical) 20ns
Signal duration l (typical) 500ms
Table 13: 1PPS signal characterization with active antenna with filter at 22°C
Signal delay d (typical) 90ns
Standard deviation σ
d
(typical) 20ns
Signal duration l (typical) 500ms
Table 14: 1PPS signal characterization with passive antenna at 22°C
The standard deviation is a probability measure for the occurrence of value within a
certain range. 68.3% of all new values will be within 1
σ of the expected value,
95.5% within 2 σ .
11.8 Reset Signal
The nRST pin is an input pin.
The nRST pin can be used to generate a reset on the A1029 modules. Resetting
the module will result in a restart of the complete firmware including the boot loader.
All information stored in flash memory will still be valid. The RTC will keep on run-
ning. The same result can be achieved using the ENABLE pin. Therefore connect-
ing nRST is not necessary.
In case of low power mode (ENABLE pin low) DO NOT pull nRST to low. This will
result in additional current draw.