From e11185d47d0a2fea6d2782761edd5fd489541512 Mon Sep 17 00:00:00 2001 From: Gareth McMullin Date: Sat, 7 Jan 2012 16:58:23 +1300 Subject: [PATCH] Fix setting alternate port functions on the STM32F4. Thanks to Ricardo Martins. --- include/libopencm3/stm32/f4/gpio.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/include/libopencm3/stm32/f4/gpio.h b/include/libopencm3/stm32/f4/gpio.h index 3fe564e4..20901d08 100644 --- a/include/libopencm3/stm32/f4/gpio.h +++ b/include/libopencm3/stm32/f4/gpio.h @@ -232,7 +232,7 @@ /* See Datasheet Table 6 (pg. 48) for alternate function mappings. */ #define GPIO_AFR(n, af) (af << ((n) * 4)) -#define GPIO_AFR_MASK(n) (0xf << ((n) * 4)) +#define GPIO_AFR_MASK(n) ~(0xf << ((n) * 4)) #define GPIO_AF0 0x0 #define GPIO_AF1 0x1 #define GPIO_AF2 0x2