From 20031f941e72ce9eaaed40d155f07c679395deb6 Mon Sep 17 00:00:00 2001
From: Michael Hayes <michael.hayes@canterbury.ac.nz>
Date: Fri, 6 Sep 2013 10:57:43 +1200
Subject: [PATCH] Increase delay when polling navswitch

---
 drivers/navswitch.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/navswitch.c b/drivers/navswitch.c
index 723eef0..00fca44 100644
--- a/drivers/navswitch.c
+++ b/drivers/navswitch.c
@@ -127,8 +127,10 @@ navswitch_update (void)
         /* I'm unsure why this is needed.  It wasn't required for the
            slightly slower PIO implementation.  There may be a minimum
            number of CPU clock cycles for the synchronising flip flops
-           to propagate the input state?  */
-        DELAY_US (1.0);
+           to propagate the input state?  For some reason the boards
+           made in 2013 need a longer delay.  Increasing the charge
+           time before switching to an input does not help.*/
+        DELAY_US (2.0); 
 
         navswitch_state[i].current = pio_input_get (navswitch_cfg[i].pio) == 0;