#define ISR_EMPTY (u8)0x00 // no bits set in ISR
-#define ISR_DOORBELL_ACK (u8)0x01 // the doorbell i sent has been recieved.
+#define ISR_DOORBELL_ACK (u8)0x01 // the doorbell i sent has been received.
#define ISR_DOORBELL_PEND (u8)0x02 // doorbell for me