diff --git a/I7000/i7000_cdp.c b/I7000/i7000_cdp.c
index 004b194..c1e2cc0 100644
--- a/I7000/i7000_cdp.c
+++ b/I7000/i7000_cdp.c
@@ -34,7 +34,7 @@
 #include "sim_defs.h"
 #ifdef NUM_DEVS_CDP
 
-#define UNIT_CDP        UNIT_ATTABLE | UNIT_DISABLE | MODE_026
+#define UNIT_CDP        UNIT_ATTABLE | UNIT_DISABLE | UNIT_SEQ | MODE_026
 
 
 /* Flags for punch and reader. */
diff --git a/I7000/i7000_lpr.c b/I7000/i7000_lpr.c
index b471dd5..21f7879 100644
--- a/I7000/i7000_lpr.c
+++ b/I7000/i7000_lpr.c
@@ -34,7 +34,7 @@
 #include "sim_defs.h"
 #ifdef NUM_DEVS_LPR
 
-#define UNIT_LPR        UNIT_ATTABLE | UNIT_DISABLE
+#define UNIT_LPR        UNIT_ATTABLE | UNIT_DISABLE | UNIT_SEQ
 
 
 /* Flags for line printer. */
diff --git a/I7000/i7090_cdp.c b/I7000/i7090_cdp.c
index 00205e1..9fce8ea 100644
--- a/I7000/i7090_cdp.c
+++ b/I7000/i7090_cdp.c
@@ -26,7 +26,7 @@
 #include "i7090_defs.h"
 #include "sim_card.h"
 #ifdef NUM_DEVS_CDP
-#define UNIT_CDP        UNIT_ATTABLE | UNIT_DISABLE
+#define UNIT_CDP        UNIT_ATTABLE | UNIT_DISABLE | UNIT_SEQ
 
 
 /* std devices. data structures
diff --git a/I7000/i7090_lpr.c b/I7000/i7090_lpr.c
index 3295535..aebc75b 100644
--- a/I7000/i7090_lpr.c
+++ b/I7000/i7090_lpr.c
@@ -40,7 +40,7 @@
 
 #ifdef NUM_DEVS_LPR
 
-#define UNIT_LPR        UNIT_ATTABLE | UNIT_DISABLE
+#define UNIT_LPR        UNIT_ATTABLE | UNIT_DISABLE | UNIT_SEQ
 #define ECHO            (1 << UNIT_V_LOCAL)