From 33e7bb7f66bc7c97834e32d285faac492414b716 Mon Sep 17 00:00:00 2001
From: SemvdH <45453592+SemvdH@users.noreply.github.com>
Date: Fri, 27 Oct 2023 09:43:01 +0200
Subject: [PATCH] Update obd2_timer.c, add comment about clearing status
 register

added reference to datasheet section 13.4
---
 due_obd2/obd2_timer.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/due_obd2/obd2_timer.c b/due_obd2/obd2_timer.c
index 4f5b5c6..d5d7f67 100644
--- a/due_obd2/obd2_timer.c
+++ b/due_obd2/obd2_timer.c
@@ -20,7 +20,9 @@ void obd2_timer_reset()
   */
   /* disable interrupts */
   RTT->RTT_MR &= ~RTT_MR_ALMIEN;
-  /* clear the status register */
+  /* clear the status register (reading it clears it)
+    SAM3X datasheet section 13.4: Reading the RTT_SR status register resets the RTTINC and ALMS fields.
+  */
   RTT->RTT_SR;
   /* set the alarm value to 0*/
   RTT->RTT_AR = 0;
@@ -29,4 +31,4 @@ void obd2_timer_reset()
   /* reset the RTT*/
   RTT->RTT_MR |= RTT_MR_RTTRST;
 
-}
\ No newline at end of file
+}