1 files changed, 53 insertions, 0 deletions
diff --git a/src/matrix.c b/src/matrix.c
new file mode 100644
index 0000000..1da8289
--- /dev/null
+++ b/src/matrix.c
@@ -0,0 +1,53 @@
+#include "keymap.h"
+
+#include "matrix.h"
+#include "pico/types.h"
+#include "hardware/gpio.h"
+#include "hardware/timer.h"
+
+#include <string.h>
+
+static const uint matrix_row_pins[] = { 4, 5, 6, 7 };
+static const uint matrix_col_pins[] = { 29, 28, 27, 26, 22, 20 };
+static_assert(ARRLEN(matrix_row_pins) == KEY_ROWS);
+static_assert(ARRLEN(matrix_col_pins) == KEY_COLS);
+
+bool prev_state_matrix[KEY_COUNT];
+bool state_matrix[KEY_COUNT];
+
+void
+matrix_init(void)
+{
+	uint x, y;
+
+	for (y = 0; y < KEY_ROWS; y++) {
+		gpio_init(matrix_row_pins[y]);
+		gpio_set_dir(matrix_row_pins[y], GPIO_IN);
+		gpio_pull_up(matrix_row_pins[y]);
+	}
+
+	for (x = 0; x < KEY_COLS; x++) {
+		gpio_init(matrix_col_pins[x]);
+		gpio_set_dir(matrix_col_pins[x], GPIO_OUT);
+	}
+}
+
+void
+scan_matrix(void)
+{
+	bool pressed;
+	uint x, y;
+
+	memcpy(prev_state_matrix, state_matrix, sizeof(state_matrix));
+
+	for (y = 0; y < KEY_ROWS; y++) {
+		for (x = 0; x < KEY_COLS; x++) {
+			gpio_put(matrix_col_pins[x], 0);
+			busy_wait_us(5);
+			pressed = !gpio_get(matrix_row_pins[y]);
+			state_matrix[y * KEY_COLS + x] = pressed;
+			gpio_put(matrix_col_pins[x], 1);
+			busy_wait_us(5);
+		}
+	}
+}