test your keys!

examples/key_demo.rs

@@ -0,0 +1,41 @@
+#![feature(start)]
+#![no_std]
+
+extern crate gba;
+use gba::{io_registers::*, video_ram::*};
+
+#[cfg(not(test))]
+#[panic_handler]
+fn panic(_info: &core::panic::PanicInfo) -> ! {
+  loop {}
+}
+
+#[start]
+fn main(_argc: isize, _argv: *const *const u8) -> isize {
+  let mode3bg2 = {
+    let mut setting = DisplayControlSetting::default();
+    setting.set_display_bg2(true);
+    setting.set_mode(DisplayControlMode::Bitmap3);
+    setting
+  };
+  set_display_control(mode3bg2);
+
+  let red = rgb16(31, 0, 0);
+  let green = rgb16(0, 31, 0);
+
+  loop {
+    let this_frame_keys = key_input();
+
+    let this_frame_key_raw: u16 = unsafe { core::mem::transmute(this_frame_keys) };
+
+    wait_until_vblank();
+
+    for i in 0..16 {
+      let key = ((this_frame_key_raw >> i) & 1) > 0;
+      mode3_draw_pixel(15 - i, 0, if key { green } else { red });
+      mode3_draw_pixel(15 - i, 1, if key { green } else { red });
+    }
+
+    wait_until_vdraw();
+  }
+}