ao_add_stdio(char (*pollchar)(void),
void (*putchar)(char) __reentrant,
void (*flush)(void)) __reentrant;
ao_add_stdio(char (*pollchar)(void),
void (*putchar)(char) __reentrant,
void (*flush)(void)) __reentrant;
-/* Shared by USB, so the USB code calls this function */
+/* If bt_link is on P2, this interrupt is shared by USB, so the USB
+ * code calls this function. Otherwise, it's a regular ISR.
+ */
+