Initial Release

adc/hello_adc/hello_adc.c

@@ -0,0 +1,30 @@
+/**
+ * Copyright (c) 2020 Raspberry Pi (Trading) Ltd.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <stdio.h>
+#include "pico/stdlib.h"
+#include "hardware/gpio.h"
+#include "hardware/adc.h"
+
+int main() {
+    stdio_init_all();
+    printf("ADC Example, measuring GPIO26\n");
+
+    adc_init();
+
+    // Make sure GPIO is high-impedance, no pullups etc
+    adc_gpio_init(26);
+    // Select ADC input 0 (GPIO26)
+    adc_select_input(0);
+
+    while (1) {
+        // 12-bit conversion, assume max value == ADC_VREF == 3.3 V
+        const float conversion_factor = 3.3f / (1 << 12);
+        uint16_t result = adc_read();
+        printf("Raw value: 0x%03x, voltage: %f V\n", result, result * conversion_factor);
+        sleep_ms(500);
+    }
+}