+#define SR1_PECERR 12
+#define SR1_OVR 11
+#define SR1_AF 10
+#define SR1_ARLO 9
+#define SR1_BERR 8
+#define SR1_TXE 7
+#define SR1_RXE 6
+#define SR1_ADDR 1
+#define SR1_BTF 2
+#define SR1_SB 0
+
+#define SR2_TRA 2
+#define SR2_BUSY 1
+#define SR2_MSL 0
+
+
+#define SR1_ERR_MASK (BV(SR1_PECERR) | \
+ BV(SR1_OVR) | \
+ BV(SR1_AF) | \
+ BV(SR1_ARLO) | \
+ BV(SR1_BERR))