[dac] Add basic STM32F4 driver

src/modm/platform/dac/stm32/dac.hpp

@@ -0,0 +1,123 @@
+#ifndef MODM_STM32_DAC_HPP
+#define MODM_STM32_DAC_HPP
+
+#include <stdint.h>
+#include "../device.hpp"
+#include <modm/platform/gpio/connector.hpp>
+
+namespace modm {
+
+namespace platform {
+
+/**
+ * Digital-to-Analog Converter (DAC)
+ *
+ * Supports simple synchronous access to the 2-channel DAC found on most STM32
+ * microcontrollers.
+ *
+ * @author Jeff McBride
+ * @ingroup modm_platform_dac
+ */
+class Dac {
+public:
+	/**
+	 * The DAC has two output channels, Channel1 and Channel2
+	 */
+	enum class Channel : uint8_t {
+		Channel1 = 0,
+		Channel2 = 1
+	};
+
+	template< template<Peripheral _> class... Signals >
+	static void
+	connect()
+	{
+		using Connector = GpioConnector<Peripheral::Dac, Signals...>;
+		Connector::connect();
+	}
+
+	/**
+	 * Initialize the D/A converter.
+	 *
+	 * Enables the RCC clock output for the DAC
+	 */
+	static inline void initialize();
+
+	/** Enable DAC output for the given channel
+	 *
+	 * @param chan    The channel to be enabled
+	 *
+	 * @pre The DAC clock must be enabled with initialize()
+	 */
+	static inline void enableChannel(Channel chan);
+
+	/**
+	 * Disable DAC output for the given channel
+	 *
+	 * @param chan    The channel to be disabled
+	 *
+	 * @pre The DAC clock must be enabled with initialize()
+	 */
+	static inline void disableChannel(Channel chan);
+
+	/**
+	 * Control the output buffer setting
+	 *
+	 * @param chan    The channel to enable/disable the output buffer on
+	 * @param enable  true to turn on the output buffer, false to turn it off
+	 *
+	 * @pre The DAC clock must be enabled with initialize()
+	 */
+	static inline void enableOutputBuffer(Channel chan, bool enable);
+
+	/**
+	 * Set the output voltage for a DAC channel
+	 *
+	 * @param chan    The channel to set
+	 * @param value   The 12-bit DAC output value, range 0-4095.
+	 *
+	 * @pre The DAC clock must be enabled with initialize()
+	 */
+	static inline void setOutput(Channel chan, uint16_t value);
+
+	/**
+	 * Set output value for Channel1
+	 *
+	 * Equivalent to setOutput(modm::platform::Dac::Channel1, value)
+	 *
+	 * @param value   The 12-bit DAC output value, range 0-4095
+	 *
+	 * @pre The DAC clock must be enabled with initialize()
+	 */
+	static inline void setOutput1(uint16_t value);
+
+	/**
+	 * Set output value for Channel2
+	 *
+	 * Equivalent to setOutput(modm::platform::Dac::Channel2, value)
+	 *
+	 * @param value   The 12-bit DAC output value, range 0-4095
+	 *
+	 * @pre The DAC clock must be enabled with initialize()
+	 */
+	static inline void setOutput2(uint16_t value);
+
+	/// Get the channel for a Pin
+	template< class Gpio >
+	static inline constexpr Channel
+	getPinChannel()
+	{
+		constexpr int8_t channel{Gpio::template DacChannel<Peripheral::Dac>};
+		static_assert(channel >= 0, "Dac does not have a channel for this pin!");
+		return Channel(channel);
+	}
+
+};
+
+} // namespace platform
+
+} // namespace modm
+
+#include "dac_impl.hpp"
+
+#endif // MODM_STM32_DAC_HPP

src/modm/platform/dac/stm32/dac_impl.hpp

@@ -0,0 +1,68 @@
+#ifndef MODM_STM32_DAC_HPP
+#	error 	"Don't include this file directly, use 'dac.hpp' instead!"
+#endif
+
+#include <modm/platform/clock/rcc.hpp>
+
+void modm::platform::Dac::initialize() {
+	Rcc::enable<Peripheral::Dac>();
+}
+
+void modm::platform::Dac::enableChannel(Channel chan) {
+	switch(chan) {
+	case Channel::Channel1:
+		DAC1->CR |= DAC_CR_EN1_Msk;
+		break;
+	case Channel::Channel2:
+		DAC1->CR |= DAC_CR_EN2_Msk;
+		break;
+	}
+}
+
+void modm::platform::Dac::disableChannel(Channel chan) {
+	switch(chan) {
+	case Channel::Channel1:
+		DAC1->CR &= ~DAC_CR_EN1_Msk;
+		break;
+	case Channel::Channel2:
+		DAC1->CR &= ~DAC_CR_EN2_Msk;
+		break;
+	}
+}
+
+void modm::platform::Dac::enableOutputBuffer(Channel chan, bool enable) {
+	uint32_t chanShift = 0;
+	switch(chan) {
+		case Channel::Channel1:
+			chanShift = 0;
+			break;
+		case Channel::Channel2:
+			chanShift = 16;
+			break;
+	};
+
+	if(enable) {
+		DAC1->CR &= ~(DAC_CR_BOFF1_Msk << chanShift);
+	} else {
+		DAC1->CR |= DAC_CR_BOFF1_Msk << chanShift;
+	}
+}
+
+void modm::platform::Dac::setOutput(Channel chan, uint16_t value) {
+	switch(chan) {
+		case Channel::Channel1:
+			DAC1->DHR12R1 = value & DAC_DHR12R1_DACC1DHR_Msk;
+			break;
+		case Channel::Channel2:
+			DAC1->DHR12R2 = value & DAC_DHR12R2_DACC2DHR_Msk;
+			break;
+	}
+}
+
+void modm::platform::Dac::setOutput1(uint16_t value) {
+	setOutput(Channel::Channel1, value);
+}
+
+void modm::platform::Dac::setOutput2(uint16_t value) {
+	setOutput(Channel::Channel2, value);
+}

src/modm/platform/dac/stm32/module.lb

@@ -0,0 +1,24 @@
+#!/usr/bin/env python3
+# -*- coding: utf-8 -*-
+
+import os
+
+def init(module):
+    module.name = ":platform:dac"
+    module.description = "Digital-to-Analog Converter (DAC)"
+
+def prepare(module, options):
+    if not options[":target"].has_driver("dac:stm32"):
+        return False
+
+    if not options[":target"].identifier.family == 'f4':
+        return False
+
+    module.depends(":cmsis:device")
+
+    return True
+
+def build(env):
+    env.outbasepath = "modm/src/modm/platform/dac"
+    env.copy("dac.hpp")
+    env.copy("dac_impl.hpp")

src/modm/platform/gpio/stm32/pin.hpp.in

@@ -209,6 +209,8 @@ public:
 private:
 	template< Peripheral peripheral >
 	static constexpr int8_t AdcChannel = -1;
+	template< Peripheral peripheral >
+	static constexpr int8_t DacChannel = -1;
 };
 
 /// @cond
@@ -245,6 +247,13 @@ template<>
 constexpr int8_t
 Gpio{{ port ~ pin }}::AdcChannel<Peripheral::{{ signal.driver }}> = {{ signal.name | to_adc_channel }};
 		%% endif
+
+		%% if signal.driver.startswith("Dac") and signal.name.startswith("Out")
+template<>
+constexpr int8_t
+Gpio{{ port ~ pin }}::DacChannel<Peripheral::{{ signal.driver }}> = {{ signal.name | to_adc_channel }};
+		%% endif
+
 	%% endfor
 
 %% endfor