diff --git a/PDP10/ka10_dkb.c b/PDP10/ka10_dkb.c
index 2b044a0..df12247 100644
--- a/PDP10/ka10_dkb.c
+++ b/PDP10/ka10_dkb.c
@@ -399,13 +399,27 @@ int dkb_keys (SIM_KEY_EVENT *kev, UNIT *uptr)
   }
 }
 
+uint32 dkb_line (SIM_KEY_EVENT *kev)
+{
+#if NUM_DEVS_III
+    if (kev->dev == &iii_dev)
+        return iii_keyboard_line ((void *)kev->vptr);
+#endif
+#if NUM_DEVS_DD
+    if (kev->dev == &dd_dev)
+        return dd_keyboard_line ((void *)kev->vptr);
+#endif
+    return ~0U;
+}
+
 int dkb_keyboard (SIM_KEY_EVENT *kev)
 {
     sim_debug(DEBUG_DETAIL, &dkb_dev, "DKB key %d %o\n", kev->key, kev->state);
     if (dkb_modifiers (kev))
       return 0;
 
-    if (dkb_keys (kev, &dkb_unit[0])) {
+    dkb_unit[0].LINE = dkb_line (kev);
+    if (dkb_unit[0].LINE != ~0U && dkb_keys (kev, &dkb_unit[0])) {
       dkb_unit[0].DATA |= VALID;
       dkb_unit[0].STATUS |= DONE;
       set_interrupt(DKB_DEVNUM, dkb_unit[0].PIA);
@@ -427,12 +441,12 @@ t_stat dkb_reset( DEVICE *dptr)
 
 t_stat dkb_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr)
 {
-    fprintf (stderr, "This is the keyboard input for the Stanford III display\n");
+    fprintf (stderr, "Keyboard input for the Stanford III and Data Disc displays\n");
     return SCPE_OK;
 }
 
 const char *dkb_description (DEVICE *dptr)
 {
-    return "Keyboard scanner for III display devices";
+    return "Keyboard scanner for III and DD display devices";
 }
 #endif
diff --git a/PDP10/ka10_iii.c b/PDP10/ka10_iii.c
index 167b57b..341a1b6 100644
--- a/PDP10/ka10_iii.c
+++ b/PDP10/ka10_iii.c
@@ -635,6 +635,12 @@ skip_up:
      return SCPE_OK;
 }
 
+uint32 iii_keyboard_line (void *p)
+{
+    /* III keyboards are 0 to 5, but only one is supported now. */
+    return 0;
+}
+
 t_stat iii_reset (DEVICE *dptr)
 {
     if (dptr->flags & DEV_DIS) {
diff --git a/PDP10/kx10_defs.h b/PDP10/kx10_defs.h
index 0defc7d..75da569 100644
--- a/PDP10/kx10_defs.h
+++ b/PDP10/kx10_defs.h
@@ -846,6 +846,9 @@ extern UNIT     auxcpu_unit[];
 //int slave_write (t_addr addr, uint64);
 //extern UNIT     slave_unit[];
 #endif
+#if NUM_DEVS_III
+extern uint32 iii_keyboard_line (void *);
+#endif
 #if NUM_DEVS_DD
 extern uint32 dd_keyboard_line (void *);
 #endif