1 files changed, 7 insertions, 2 deletions
diff --git a/files.mk b/files.mk
index dca418b..ef1feaa 100644
--- a/files.mk
+++ b/files.mk
@@ -1,6 +1,11 @@
+ifndef IOE_PREFIX
+	IOE_PREFIX = .
+endif
 
-IOE_SPI_SRC = $(IOE_PREFIX)/src/avr5/spi.c
-IOE_SPI_USI_SRC = $(IOE_PREFIX)/src/avr25/spi_usi.c
+IOE_SPI_SRC = $(IOE_PREFIX)/src/spi.c
+IOE_SPI_USI_SRC = $(IOE_PREFIX)/src/spi_usi.c
+IOE_SPI_USART_SRC = $(IOE_PREFIX)/src/spi_usart.c
 
 IOE_SPI_OBJ = $(patsubst %.c,%.o,$(IOE_SPI_SRC))
 IOE_SPI_USI_OBJ = $(patsubst %.c,%.o,$(IOE_SPI_USI_SRC))
+IOE_SPI_USART_OBJ = $(patsubst %.c,%.o,$(IOE_SPI_USART_SRC))