diff --git a/src/system/itsdev.976 b/src/system/itsdev.976
index 23cf122a..3b8efe44 100755
--- a/src/system/itsdev.976
+++ b/src/system/itsdev.976
@@ -2088,7 +2088,7 @@ INARK:	SETOM POTUSR(A)	;THIS POT A LOSER, FLUSH
 	SOS POTCON
 	SOS IMPXF
 	SOSGE IMXNTO
-	DATAO DSDEVN,[MPX]
+IFDEF DSDP,DATAO DSDEVN,[MPX]
 	JRST UPOTR		;RETURN FOR MORE POTS
 
 UPOT4:	HRREI C,-6(B)		;C_DELTA-6
@@ -4600,7 +4600,7 @@ AIMXW5:	IDIVI A,3
 IMPXCL:	TRNE A,4	;SKIP ON WAS READING AT MP
 IMXCL1:	SOS IMPXF	;WAS READING AT PI
 	SOSGE IMXNTO
-	DATAO DSDEVN,[MPX]
+IFDEF DSDP,DATAO DSDEVN,[MPX]
 	POPJ P,
 
 IMPXRS:	SETOM MPXWF
@@ -4726,7 +4726,7 @@ OMPXS:	XCTR XRW,[DATAO OMPX,(C)]	;ZAP CHNL
 	POPJ P,
 
 OMPXCL:	SOSGE OMXNTO
-	DATAO DSDEVN,[OMPX]
+IFDEF DSDP,DATAO DSDEVN,[OMPX]
 	POPJ P,
 
 EBLK