diff --git a/firmware/slavechip/Makefile b/firmware/slavechip/Makefile
index 1846ba1..aef3d40 100644
--- a/firmware/slavechip/Makefile
+++ b/firmware/slavechip/Makefile
@@ -24,7 +24,7 @@ flash:	all
 	avrdude -c usbasp -p m88 -U flash:w:firmware.hex
 
 fuses:
-	avrdude -c usbasp -p m88 -U lfuse:w:0xdf:m -U hfuse:w:0xde:m # external oscillator
+	avrdude -c usbasp -p m88 -U lfuse:w:0xe2:m -U hfuse:w:0xdf:m -U efuse:w:0xf9:m 
 
 
 ## what are the source dependencies