diff --git a/makefile b/makefile
index ccfcd8fa..3f8a5703 100644
--- a/makefile
+++ b/makefile
@@ -466,7 +466,7 @@ VAX = ${VAXD}/vax_cpu.c ${VAXD}/vax_cpu1.c ${VAXD}/vax_fpa.c ${VAXD}/vax_io.c \
 	${PDP11D}/pdp11_rl.c ${PDP11D}/pdp11_rq.c ${PDP11D}/pdp11_ts.c \
 	${PDP11D}/pdp11_dz.c ${PDP11D}/pdp11_lp.c ${PDP11D}/pdp11_tq.c \
 	${PDP11D}/pdp11_xq.c ${PDP11D}/pdp11_ry.c ${PDP11D}/pdp11_vh.c \
-	${PDP11D}/pdp11_cr.c ${PDP11D}/pdp11_io_lib.c
+	${PDP11D}/pdp11_cr.c ${PDP11D}/pdp11_dmc.c ${PDP11D}/pdp11_io_lib.c
 VAX_OPT = -DVM_VAX -DUSE_INT64 -DUSE_ADDR64 -I ${VAXD} -I ${PDP11D} ${NETWORK_OPT}