dac

Author: soburi

cores/arduino/Arduino.h

@@ -105,9 +105,6 @@ enum analogPins {
 	DT_FOREACH_PROP_ELEM(DT_PATH(zephyr_user), adc_pin_gpios, AN_ENUMS)
 };
 
-// We provide analogReadResolution APIs
-void analogReadResolution(int bits);
-
 #endif
 
 #ifdef CONFIG_DAC
@@ -119,7 +116,10 @@ void analogReadResolution(int bits);
 #define DAC_ENUMS(n, p, i) DAC##i = i,
 
 enum dacPins {
-	DT_FOREACH_PROP_ELEM(DT_PATH(zephyr_user), dac_channels, DAC_ENUMS) NUM_OF_DACS
+#if DT_NODE_HAS_PROP(DT_PATH(zephyr_user), dac_channels)
+	DT_FOREACH_PROP_ELEM(DT_PATH(zephyr_user), dac_channels, DAC_ENUMS)
+#endif
+	NUM_OF_DACS
 };
 
 #endif
@@ -134,8 +134,14 @@ int digitalPinToInterrupt(pin_size_t pin);
 #define portOutputRegister(x)  (x)
 #define portInputRegister(x)   (x)
 
+#if defiend(CONFIG_ADC)
+// We provide analogReadResolution APIs
 void analogReadResolution(int bits);
+#endif
+
+#if defined(CONFIG_ADC) || defined(CONFIG_DAC)
 void analogWriteResolution(int bits);
+#endif
 
 #include <variant.h>
 

cores/arduino/zephyrCommon.cpp

@@ -189,7 +189,10 @@ static const struct device *const dac_dev = DEVICE_DT_GET(DAC_NODE);
 	},
 
 static const struct dac_channel_cfg dac_ch_cfg[] = {
-	DT_FOREACH_PROP_ELEM(DT_PATH(zephyr_user), dac_channels, DAC_CHANNEL_DEFINE)};
+#if DT_NODE_HAS_PROP(DT_PATH(zephyr_user), dac_channels)
+	DT_FOREACH_PROP_ELEM(DT_PATH(zephyr_user), dac_channels, DAC_CHANNEL_DEFINE)
+#endif
+};
 
 #endif
 
@@ -342,16 +345,46 @@ void analogWrite(pin_size_t pinNumber, int value) {
 #endif
 
 #ifdef CONFIG_DAC
+static bool dac_channel_initialized[NUM_OF_DACS];
+
 void analogWrite(enum dacPins dacName, int value) {
+#if DT_NODE_HAS_PROP(DT_PATH(zephyr_user), dac_channels)
+	int ret = 0;
+
 	if (dacName >= NUM_OF_DACS) {
 		return;
 	}
 
-	dac_channel_setup(dac_dev, &dac_ch_cfg[dacName]);
+	if (!dac_channel_initialized[dacName]) {
+		if (!device_is_ready(dac_dev)) {
+			return;
+		}
+
+		ret = dac_channel_setup(dac_dev, &dac_ch_cfg[dacName]);
+		if (ret != 0) {
+			return;
+		}
+		dac_channel_initialized[dacName] = true;
+	}
+
+	const uint32_t max_dac_value = (1U << dac_ch_cfg[dacName].resolution) - 1U;
+	const uint32_t maxInput = (1U << _analog_write_resolution) - 1U;
 
-	const int max_dac_value = 1U << dac_ch_cfg[dacName].resolution;
-	dac_write_value(dac_dev, dac_ch_cfg[dacName].channel_id,
-					map(value, 0, 1 << _analog_write_resolution, 0, max_dac_value));
+	if (value < 0) {
+		value = 0;
+	} else if (static_cast<uint32_t>(value) > maxInput) {
+		value = static_cast<int>(maxInput);
+	}
+
+	ret = dac_write_value(
+		dac_dev,
+		dac_ch_cfg[dacName].channel_id,
+		static_cast<uint32_t>(map(static_cast<long>(value),
+								  0L,
+								  static_cast<long>(maxInput),
+								  0L,
+								  static_cast<long>(max_dac_value))));
+#endif
 }
 #endif