From da395cc9224f57300d8b05b8369f08d202f5c184 Mon Sep 17 00:00:00 2001 From: Sylvain Munaut Date: Thu, 1 Sep 2022 18:15:42 +0200 Subject: [PATCH] icE1usb fw/gpsdo: If no PPS present for >= 3s, go to hold over mode Signed-off-by: Sylvain Munaut Change-Id: Ia85a8bb0e146cb117ea6e2704c6a4dedf215c75a --- firmware/ice40-riscv/icE1usb/gpsdo.c | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/firmware/ice40-riscv/icE1usb/gpsdo.c b/firmware/ice40-riscv/icE1usb/gpsdo.c index 573c0bb..2481c2e 100644 --- a/firmware/ice40-riscv/icE1usb/gpsdo.c +++ b/firmware/ice40-riscv/icE1usb/gpsdo.c @@ -15,6 +15,8 @@ #include "ice1usb_proto.h" +#include "config.h" + struct { /* Configuration */ @@ -275,6 +277,14 @@ gpsdo_poll(void) uint32_t tick_now, tick_diff; bool valid; + /* If more than 3 sec elapsed since last PPS, go to hold-over */ + if (time_elapsed(g_gpsdo.meas.tick_prev, 3 * SYS_CLK_FREQ)) { + g_gpsdo.state = STATE_HOLD_OVER; + g_gpsdo.meas.invalid = 0; + g_gpsdo.meas.skip = 0; + return; + } + /* Get current tick and check if there was a PPS and estimate frequency */ tick_now = time_pps_read(); @@ -299,6 +309,7 @@ gpsdo_poll(void) /* No GPS fix, go to hold-over */ g_gpsdo.state = STATE_HOLD_OVER; g_gpsdo.meas.invalid = 0; + g_gpsdo.meas.skip = 0; return; }