add warning about external wake on old board rev

diff --git a/watch-library/watch/watch_deepsleep.c b/watch-library/watch/watch_deepsleep.c
index 89d66ee764226ff19c5e14642a11ecd0643726b6..dda428f5f570480635cdadf0bab9268b9e92b2dd 100644 (file)
--- a/watch-library/watch/watch_deepsleep.c
+++ b/watch-library/watch/watch_deepsleep.c
@@ -22,6 +22,13 @@
  * SOFTWARE.
  */
 
+// this warning only appears when you `make BOARD=OSO-SWAT-A1-02`. it's annoying,
+// but i'd rather have it warn us at build-time than fail silently at run-time.
+// besides, no one but me really has any of these boards anyway.
+#warning This board revision does not support external wake on BTN_ALARM, so watch_register_extwake_callback will not work with it. Use watch_register_interrupt_callback instead.
+#if BTN_ALARM != GPIO(GPIO_PORTA, 2)
+#endif
+
 static void extwake_callback(uint8_t reason);
 ext_irq_cb_t btn_alarm_callback;
 ext_irq_cb_t a2_callback;