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diff --git a/libmaple/dac.c b/libmaple/dac.c
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+/******************************************************************************
+ * The MIT License
+ *
+ * Copyright (c) 2010 Bryan Newbold.
+ * Copyright (c) 2011, 2012 LeafLabs, LLC.
+ *
+ * Permission is hereby granted, free of charge, to any person
+ * obtaining a copy of this software and associated documentation
+ * files (the "Software"), to deal in the Software without
+ * restriction, including without limitation the rights to use, copy,
+ * modify, merge, publish, distribute, sublicense, and/or sell copies
+ * of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ *****************************************************************************/
+
+/**
+ * @file libmaple/dac.c
+ * @brief Digital to analog converter support.
+ */
+
+#include <libmaple/dac.h>
+#include <libmaple/libmaple.h>
+#include <libmaple/gpio.h>
+
+#if STM32_HAVE_DAC
+dac_dev dac = {
+    .regs = DAC_BASE,
+};
+const dac_dev *DAC = &dac;
+#endif
+
+/**
+ * @brief Initialize the digital to analog converter
+ * @param dev DAC device
+ * @param flags Flags:
+ *      DAC_CH1: Enable channel 1
+ *      DAC_CH2: Enable channel 2
+ * @sideeffect May set PA4 or PA5 to INPUT_ANALOG
+ */
+void dac_init(const dac_dev *dev, uint32 flags) {
+    /* First turn on the clock */
+    rcc_clk_enable(RCC_DAC);
+    rcc_reset_dev(RCC_DAC);
+
+    if (flags & DAC_CH1) {
+        dac_enable_channel(dev, 1);
+    }
+
+    if (flags & DAC_CH2) {
+        dac_enable_channel(dev, 2);
+    }
+}
+
+/**
+ * @brief Write a 12-bit value to the DAC to output
+ * @param dev DAC device
+ * @param channel channel to select (1 or 2)
+ * @param val value to write
+ */
+void dac_write_channel(const dac_dev *dev, uint8 channel, uint16 val) {
+    switch(channel) {
+    case 1:
+        dev->regs->DHR12R1 = DAC_DHR12R1_DACC1DHR & val;
+        break;
+    case 2:
+        dev->regs->DHR12R2 = DAC_DHR12R2_DACC2DHR & val;
+        break;
+    }
+}
+
+/**
+ * @brief Enable a DAC channel
+ * @param dev DAC device
+ * @param channel channel to enable, either 1 or 2
+ * @sideeffect May change pin mode of PA4 or PA5
+ */
+void dac_enable_channel(const dac_dev *dev, uint8 channel) {
+    /*
+     * Setup ANALOG mode on PA4 and PA5. This mapping is consistent
+     * across all supported STM32s with a DAC.
+     */
+    switch (channel) {
+    case 1:
+        gpio_set_mode(GPIOA, 4, GPIO_MODE_ANALOG);
+        dev->regs->CR |= DAC_CR_EN1;
+        break;
+    case 2:
+        gpio_set_mode(GPIOA, 5, GPIO_MODE_ANALOG);
+        dev->regs->CR |= DAC_CR_EN2;
+        break;
+    }
+}
+
+/**
+ * @brief Disable a DAC channel
+ * @param dev DAC device
+ * @param channel channel to disable, either 1 or 2
+ */
+void dac_disable_channel(const dac_dev *dev, uint8 channel) {
+    switch (channel) {
+    case 1:
+        dev->regs->CR &= ~DAC_CR_EN1;
+        break;
+    case 2:
+        dev->regs->CR &= ~DAC_CR_EN2;
+        break;
+    }
+}