SAS = $(top_builddir)/bin/asx8051
SCC = $(top_builddir)/bin/sdcc
-PORTDIR = ../build/$(PORT)
+# override PORTDIR defined by super (parent) makefile
+override PORTDIR = ../build/$(PORT)
OBJ = crtstart.rel crtxinit.rel crtxclear.rel crtclear.rel crtxstack.rel \
crtpagesfr.rel crtbank.rel crtcall.rel