diff --git a/firmware/Makefile b/firmware/Makefile
index 9c5bc57..92bfbc9 100644
--- a/firmware/Makefile
+++ b/firmware/Makefile
@@ -131,6 +131,7 @@ CSRC = $(ALLCSRC) $(BOARDDIR)/board.c
 # setting.
 CPPSRC = $(ALLCPPSRC) \
           $(BOARDDIR)/port.cpp \
+          $(BOARDDIR)/port_shared.cpp \
           shared/flash.cpp \
           can.cpp \
           can_helper.cpp \
diff --git a/firmware/boards/f1_dave/port.cpp b/firmware/boards/f1_dave/port.cpp
index c556891..15f87d0 100644
--- a/firmware/boards/f1_dave/port.cpp
+++ b/firmware/boards/f1_dave/port.cpp
@@ -54,12 +54,6 @@ AnalogResult AnalogSample()
     };
 }
 
-const CANConfig canConfig500 =
-{
-    CAN_MCR_ABOM | CAN_MCR_AWUM | CAN_MCR_TXFP,
-    0 // TODO: set bit timing! correctly!
-};
-
 Configuration GetConfiguration()
 {
     // TODO: implement me!
diff --git a/firmware/boards/f1_dave/port_shared.cpp b/firmware/boards/f1_dave/port_shared.cpp
new file mode 100644
index 0000000..f53d7a6
--- /dev/null
+++ b/firmware/boards/f1_dave/port_shared.cpp
@@ -0,0 +1,9 @@
+#include "port_shared.h"
+
+// board-specific stuff shared between bootloader and firmware
+
+const CANConfig canConfig500 =
+{
+    CAN_MCR_ABOM | CAN_MCR_AWUM | CAN_MCR_TXFP,
+    0 // TODO: set bit timing! correctly!
+};