Initial Release

adc/joystick_display/joystick_display.c

@@ -0,0 +1,40 @@
+/**
+ * Copyright (c) 2020 Raspberry Pi (Trading) Ltd.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <stdio.h>
+#include "pico/stdlib.h"
+#include "hardware/adc.h"
+
+int main() {
+    stdio_init_all();
+    adc_init();
+    // Make sure GPIO is high-impedance, no pullups etc
+    adc_gpio_init(26);
+    adc_gpio_init(27);
+
+    while (1) {
+        adc_select_input(0);
+        uint adc_x_raw = adc_read();
+        adc_select_input(1);
+        uint adc_y_raw = adc_read();
+
+        // Display the joystick position something like this:
+        // X: [            o             ]  Y: [              o         ]
+        const uint bar_width = 40;
+        const uint adc_max = (1 << 12) - 1;
+        uint bar_x_pos = adc_x_raw * bar_width / adc_max;
+        uint bar_y_pos = adc_y_raw * bar_width / adc_max;
+        printf("\rX: [");
+        for (int i = 0; i < bar_width; ++i)
+            putchar( i == bar_x_pos ? 'o' : ' ');
+        printf("]  Y: [");
+        for (int i = 0; i < bar_width; ++i)
+            putchar( i == bar_y_pos ? 'o' : ' ');
+        printf("]");
+        sleep_ms(50);
+
+    }
+}