From c50058d6a2d10e4b63fce8bfa9116b503e6dcbe5 Mon Sep 17 00:00:00 2001
From: Stephen Dwyer <scdwyer@ualberta.ca>
Date: Fri, 29 Mar 2013 16:17:01 -0600
Subject: [PATCH] [stm32][ms2100] the reset/set gpio state for the ms2100 reset
 functionality was inverted, hopefully fixes Issue #384

---
 sw/airborne/arch/stm32/peripherals/ms2100_arch.h | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/sw/airborne/arch/stm32/peripherals/ms2100_arch.h b/sw/airborne/arch/stm32/peripherals/ms2100_arch.h
index 701158e761..9e10edde6f 100644
--- a/sw/airborne/arch/stm32/peripherals/ms2100_arch.h
+++ b/sw/airborne/arch/stm32/peripherals/ms2100_arch.h
@@ -31,12 +31,20 @@
 #include <libopencm3/stm32/f1/gpio.h>
 #include "mcu_periph/spi.h"
 
+/**
+ * Here Reset indicates the Ms2100 is in normal state, i.e.
+ * the reset line is driven low (i.e. the GPIO is "reset")
+ */
 static inline void Ms2100Reset(void) {
-  GPIOC_BSRR = GPIO13;
+  GPIOC_BRR = GPIO13;
 }
 
+/**
+ * Here Set indicates the Ms2100 is in reset state, i.e.
+ * the reset line is driven high (i.e. the GPIO is "set")
+ */
 static inline void Ms2100Set(void) {
-  GPIOC_BRR = GPIO13;
+  GPIOC_BSRR = GPIO13;
 }
 
 #define Ms2100HasEOC() (gpio_get(GPIOB, GPIO5) != 0)