diff --git a/usbdux/Makefile_dux b/usbdux/Makefile_dux
index 1dc0939..16c1c73 100644
--- a/usbdux/Makefile_dux
+++ b/usbdux/Makefile_dux
@@ -3,20 +3,16 @@
 # no warranty
 #
 
-all: as31 usbduxfast_firmware.bin usbdux_firmware.bin usbduxsigma_firmware.bin
+all: usbduxfast_firmware.bin usbdux_firmware.bin usbduxsigma_firmware.bin
 
-as31:
-	make -C as31-2.1
+usbduxfast_firmware.bin: fx2-include.asm usbduxfast_firmware.asm
+	as31 -Fbin usbduxfast_firmware.asm
 
-usbduxfast_firmware.bin: fx2-include.asm usbduxfast_firmware.asm as31
-	as31-2.1/as31 -Fbin usbduxfast_firmware.asm
+usbdux_firmware.bin: fx2-include.asm usbdux_firmware.asm
+	as31 -Fbin usbdux_firmware.asm
 
-usbdux_firmware.bin: fx2-include.asm usbdux_firmware.asm as31
-	as31-2.1/as31 -Fbin usbdux_firmware.asm
-
-usbduxsigma_firmware.bin: fx2-include.asm usbduxsigma_firmware.asm as31
-	as31-2.1/as31 -Fbin usbduxsigma_firmware.asm
+usbduxsigma_firmware.bin: fx2-include.asm usbduxsigma_firmware.asm
+	as31 -Fbin usbduxsigma_firmware.asm
 
 clean:
 	rm -f *.bin *~ *.lst *.bin
-	make -C as31-2.1 clean
diff --git a/usbdux/README.dux b/usbdux/README.dux
deleted file mode 100644
index b3c8c05..0000000
--- a/usbdux/README.dux
+++ /dev/null
@@ -1,15 +0,0 @@
-To compile the firmware for the USBDUX,USBDUXfast and USBDUXsigma
------------------------------------------------------------------
-Download the as31 from:
-
-http://www.berndporr.me.uk/as31/
-
-(this is a patched version of as31 which supports an
-include directive).
-
-Install it in this directory.
-
-Then run "make -f Makefile_dux".
-
-Feedback:
-BerndPorr@f2s.com