got an interrupt-based uart interface library working
diff --git a/bbb_cape/src/cape/uart_common.h b/bbb_cape/src/cape/uart_common.h
new file mode 100644
index 0000000..bb98a07
--- /dev/null
+++ b/bbb_cape/src/cape/uart_common.h
@@ -0,0 +1,11 @@
+#ifndef CAPE_UART_COMMON_H_
+#define CAPE_UART_COMMON_H_
+
+// Configures it for baud, 1 start bit, 1 stop bit, and 1 even parity bit.
+// baud must be between 57KHz and 3.75MHz. It must be something that the USART can
+// handle exactly (see
+// <http://www.st.com/web/en/resource/technical/document/reference_manual/CD00225773.pdf#page=633>
+// or so for choices (fPCLK = 60MHz, OVER8 = 0 for now)).
+void uart_common_configure(int baud);
+
+#endif // CAPE_UART_COMMON_H_