GPS Pulse Per Second

  • HI,
    I am wondering if it is possible to access the Pulse per second (PPS) from the GPS device on an IO pin? n This is needed for some critical RT tasks where I need phase stability for many many hours.

    Is it possible to use the GPS with the RTC? Whats the accuracy/stability of the RTC? Is it temperature compensated?

    NTP time is not accurate enough for my application.

    Many thanks

  • DeveloperWorld

    Hi @NeilC

    Checking out the CXD5602GG_technical_manual shows that there are a few options for SPR_GNSS_1PPS_OUT signal.

    Looking at the schematic of the main board you can track the GNSS_1PPS_OUT signal from the CXD5602 chip on the main board out via the B2B connector to the extension board where it then ends up on something that looks like a test point called CL1. The CXD5602PWBEXT1_part_layout of the extension board will help you locating this point.

    Looking into CXD5247GF_technical_manual_02.pdf page 6 will give you and overview of the oscillator/xtal used as RTC source.

    CXD5602GG_technical_manual.pdf page 20 shows a table of Frequency tolerance for RTC clock in.

    The CXD5602_user_manual page 170 explains abit on the clock sources used for RTC.

    Hope these pointers will help you on your way. If not please let me know.


Log in to reply