diff --git a/src/mess/machine/upd765.c b/src/mess/machine/upd765.c
index 69dc7a501a3..1d53c4cfe03 100644
--- a/src/mess/machine/upd765.c
+++ b/src/mess/machine/upd765.c
@@ -280,8 +280,11 @@ READ8_MEMBER(upd765_family_device::msr_r)
 		msr |= MSR_CB;
 		if(spec & SPEC_ND)
 			msr |= MSR_EXM;
-		if(internal_drq)
+		if(internal_drq) {
 			msr |= MSR_RQM;
+			if(!fifo_write)
+				msr |= MSR_DIO;
+		}
 		break;
 
 	case PHASE_RESULT: