From 6f236f0c3b3fff4de2ad9090a06e6b758b5e00b7 Mon Sep 17 00:00:00 2001
From: rmackay9 <rmackay9@yahoo.com>
Date: Tue, 28 Aug 2012 17:29:48 +0900
Subject: [PATCH] ArduCopter: increase SPI bus speed to 2Mhz after IMU
 initialisation has completed (MPU6000 accepts maximum of 1Mhz for some
 registers but up to 20Mhz for main sensor and interrupt registers)

---
 ArduCopter/system.pde | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/ArduCopter/system.pde b/ArduCopter/system.pde
index b11ef389d1..6a4a5ad178 100644
--- a/ArduCopter/system.pde
+++ b/ArduCopter/system.pde
@@ -309,6 +309,9 @@ static void init_ardupilot()
 
     startup_ground();
 
+    // now that initialisation of IMU has occurred increase SPI to 2MHz
+    SPI.setClockDivider(SPI_CLOCK_DIV8); // 2MHZ SPI rate
+
 #if LOGGING_ENABLED == ENABLED
     Log_Write_Startup();
     Log_Write_Data(10, (float)g.pi_stabilize_roll.kP());