From c7d9054c3d7df9faa92ee5d97e572daf25b78b11 Mon Sep 17 00:00:00 2001
From: Richard Meadows <richardeoin@gmail.com>
Date: Sat, 27 Jun 2015 19:16:19 +0100
Subject: [PATCH] Align gps timepulse with the top of the utc second

---
 firmware/inc/ubx_messages.h | 16 ++++++++++++++++
 firmware/src/gps.c          |  8 ++++++--
 2 files changed, 22 insertions(+), 2 deletions(-)

diff --git a/firmware/inc/ubx_messages.h b/firmware/inc/ubx_messages.h
index 8f5062d..cd7056f 100644
--- a/firmware/inc/ubx_messages.h
+++ b/firmware/inc/ubx_messages.h
@@ -200,6 +200,22 @@ enum {
   UBX_POWERSAVE_OFF	= 0,
   UBX_POWERSAVE_ON	= 1,
 };
+/**
+ * UBX TP5 Flags
+ */
+enum {
+  UBX_TP5_ENABLE	= (1 << 0),
+  UBX_TP5_LOCK_TO_GPS	= (1 << 1),
+  UBX_TP5_LOCKED_OTHER	= (1 << 2),
+  UBX_TP5_IS_FREQ	= (1 << 3),
+  UBX_TP5_IS_LENGTH	= (1 << 4),
+  UBX_TP5_ALIGN_TO_TOW	= (1 << 5),
+  UBX_TP5_ALIGN_FALLING	= (0 << 6),
+  UBX_TP5_ALIGN_RISING  = (1 << 6),
+  UBX_TP5_USE_GRID_UTC	= (0 << 7),
+  UBX_TP5_USE_GRID_GPS	= (1 << 7),
+};
+
 
 /**
  * =============================================================================
diff --git a/firmware/src/gps.c b/firmware/src/gps.c
index 6f1fe5a..8e3bce2 100644
--- a/firmware/src/gps.c
+++ b/firmware/src/gps.c
@@ -371,8 +371,12 @@ void gps_set_timepulse_five(uint32_t frequency)
   /* Define the settings we want */
   ubx_cfg_tp5.payload.tpIdx = 0;
   ubx_cfg_tp5.payload.antCableDelay = 50; /* 50 nS	*/
-  /* GPS time, duty cyle, frequency, lock to GPS, active */
-  ubx_cfg_tp5.payload.flags = 0x80 | 0x8 | 0x3;
+
+  /* frequency, lock to GPS, active */
+  ubx_cfg_tp5.payload.flags =
+    UBX_TP5_ENABLE | UBX_TP5_LOCK_TO_GPS | UBX_TP5_IS_FREQ |
+    UBX_TP5_ALIGN_RISING | UBX_TP5_USE_GRID_UTC;
+
   ubx_cfg_tp5.payload.freqPeriod = frequency;
   ubx_cfg_tp5.payload.pulseLenRatio = 0x80000000; /* 50 % duty cycle*/