Add information w.r.t default GUS IRQ assigment
diff --git a/qemu-doc.texi b/qemu-doc.texi
index 2f566b6..99d7f0d 100644
--- a/qemu-doc.texi
+++ b/qemu-doc.texi
@@ -199,6 +199,20 @@
QEMU uses GUS emulation(GUSEMU32 @url{http://www.deinmeister.de/gusemu/})
by Tibor "TS" Schütz.
+Not that, by default, GUS shares IRQ(7) with parallel ports and so
+qemu must be told to not have parallel ports to have working GUS
+
+@example
+qemu dos.img -soundhw gus -parallel none
+@end example
+
+Alternatively:
+@example
+qemu dos.img -device gus,irq=5
+@end example
+
+Or some other unclaimed IRQ.
+
CS4231A is the chip used in Windows Sound System and GUSMAX products
@c man end
