1 files changed, 58 insertions, 0 deletions
diff --git a/source/buttons.c b/source/buttons.c
new file mode 100644
index 0000000..45ea7bd
--- /dev/null
+++ b/source/buttons.c
@@ -0,0 +1,58 @@
+/**
+ * buttons.c - Provides ability to read button state.
+ * Copyright (C) 2020  Clyne Sullivan
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ * See the GNU General Public License for more details.
+ */
+
+#include "buttons.h"
+#include "hal.h"
+
+unsigned char button_state = 0;
+
+static void buttonStateHandler(void *arg)
+{
+    int pad = (unsigned int)arg & 0xFF;
+    int bit = 1 << ((unsigned int)arg >> 8);
+
+    if (!palReadPad(GPIOA, pad)) {
+        if ((button_state & bit) != bit)
+            button_state |= bit;
+    } else {
+        if ((button_state & bit) == bit)
+            button_state &= ~(bit);
+    }
+}
+
+void buttons_init()
+{
+    palSetPadMode(GPIOA, 0, PAL_MODE_INPUT_PULLUP);   // Joy A (UL)
+    palSetPadMode(GPIOA, 1, PAL_MODE_INPUT_PULLUP);   // Joy B (UR)
+    palSetPadMode(GPIOA, 2, PAL_MODE_INPUT_PULLUP);   // Joy C (DR)
+    palSetPadMode(GPIOA, 3, PAL_MODE_INPUT_PULLUP);   // Joy D (DL)
+    palSetPadMode(GPIOA, 6, PAL_MODE_INPUT_PULLUP);   // Joy button
+    palSetPadMode(GPIOA, 7, PAL_MODE_INPUT_PULLUP);   // Button 1
+    palSetPadMode(GPIOA, 9, PAL_MODE_INPUT_PULLUP);   // Button 2
+    palSetPadMode(GPIOA, 10, PAL_MODE_INPUT_PULLUP);  // Button 3
+    palEnablePadEvent(GPIOA, 0, PAL_EVENT_MODE_BOTH_EDGES);
+    palEnablePadEvent(GPIOA, 1, PAL_EVENT_MODE_BOTH_EDGES);
+    palEnablePadEvent(GPIOA, 2, PAL_EVENT_MODE_BOTH_EDGES);
+    palEnablePadEvent(GPIOA, 3, PAL_EVENT_MODE_BOTH_EDGES);
+    palEnablePadEvent(GPIOA, 6, PAL_EVENT_MODE_BOTH_EDGES);
+    palEnablePadEvent(GPIOA, 7, PAL_EVENT_MODE_BOTH_EDGES);
+    palEnablePadEvent(GPIOA, 9, PAL_EVENT_MODE_BOTH_EDGES);
+    palEnablePadEvent(GPIOA, 10, PAL_EVENT_MODE_BOTH_EDGES);
+    palSetPadCallback(GPIOA, 0, buttonStateHandler, (void *)0x0700);
+    palSetPadCallback(GPIOA, 1, buttonStateHandler, (void *)0x0601);
+    palSetPadCallback(GPIOA, 2, buttonStateHandler, (void *)0x0502);
+    palSetPadCallback(GPIOA, 3, buttonStateHandler, (void *)0x0403);
+    palSetPadCallback(GPIOA, 6, buttonStateHandler, (void *)0x0306);
+    palSetPadCallback(GPIOA, 7, buttonStateHandler, (void *)0x0207);
+    palSetPadCallback(GPIOA, 9, buttonStateHandler, (void *)0x0109);
+    palSetPadCallback(GPIOA, 10, buttonStateHandler, (void *)0x000A);
+}
+