diff --git a/c64/kernal/iec/open_iec.s b/c64/kernal/iec/open_iec.s
index 33269eb9..f2269c0b 100644
--- a/c64/kernal/iec/open_iec.s
+++ b/c64/kernal/iec/open_iec.s
@@ -9,6 +9,10 @@
 
 open_iec:
 
+	// Check for command to send
+	ldy FNLEN
+	beq open_iec_done
+
 	// We have a command to send to IEC device
 	jsr LISTEN
 	bcc !+
@@ -28,6 +32,8 @@ open_iec:
 	// Send command ('file name')
 	jsr lvs_send_file_name
 
+open_iec_done:
+
 	jmp open_done_success
 
 
diff --git a/c64/kernal/iostack/f291.close.s b/c64/kernal/iostack/f291.close.s
index c2f3c4ae..c4930447 100644
--- a/c64/kernal/iostack/f291.close.s
+++ b/c64/kernal/iostack/f291.close.s
@@ -11,21 +11,26 @@
 
 CLOSE:
 
-	// XXX this needs more testing (opening 10 files at once, closing in various orders, etc) once the code is more mature
-
 	// Find the LAT / SAT / FAT entry which LAT corresponds to A
 
 	jsr find_fls
 	bcs close_end // XXX can we report error in IOSTATUS here?
 
-#if CONFIG_IEC
+	// We have the entry index in .Y 
 
-	// We have the entry index in .Y - check whether this is IEC device
 	lda FAT, y
+
+	// Perform device-specific actions
+
+#if HAS_RS232
+	cmp #$02
+	beq_far close_rs232
+#endif
+
+#if CONFIG_IEC
 	jsr iec_check_devnum_oc
 	bcc_far close_iec
-
-#endif // CONFIG_IEC
+#endif
 
 	// FALLTROUGH
 
diff --git a/c64/kernal/iostack/f34a.open.s b/c64/kernal/iostack/f34a.open.s
index ddadebea..3dc0e134 100644
--- a/c64/kernal/iostack/f34a.open.s
+++ b/c64/kernal/iostack/f34a.open.s
@@ -54,15 +54,22 @@ open_has_space:
 	iny
 	sty LDTND
 
-	// Check for command to send
-	lda FNLEN
-	beq open_done_success
-	
-	// Check for IEC device
 	lda FA
+
+#if HAS_RS232
+
+	cmp #$02
+	beq_far open_rs232
+
+#endif
+
+#if CONFIG_IEC
+
 	jsr iec_check_devnum_oc
 	bcc_far open_iec
 
+#endif
+	
 	// FALLTROUGH
 
 open_done_success:
diff --git a/c64/kernal/rs232/close_rs232.s b/c64/kernal/rs232/close_rs232.s
index 95e5959e..a2d6457e 100644
--- a/c64/kernal/rs232/close_rs232.s
+++ b/c64/kernal/rs232/close_rs232.s
@@ -3,14 +3,15 @@
 // RS-232 part of the CLOSE routine
 //
 
-// XXX connect to I/O stack
-
 
 #if HAS_RS232
 
 
 close_rs232:
-	STUB_IMPLEMENTATION() // XXX provide implementation for both UP2400 and UP9600
+
+	// XXX provide implementation for both UP2400 and UP960
+
+	jmp close_remove_from_table
 
 
 #endif // HAS_RS232
diff --git a/c64/kernal/rs232/open_rs232.s b/c64/kernal/rs232/open_rs232.s
index b864cdc0..82d64230 100644
--- a/c64/kernal/rs232/open_rs232.s
+++ b/c64/kernal/rs232/open_rs232.s
@@ -3,14 +3,15 @@
 // RS-232 part of the OPEN routine
 //
 
-// XXX connect to I/O stack
-
 
 #if HAS_RS232
 
 
 open_rs232:
-	STUB_IMPLEMENTATION() // XXX provide implementation for both UP2400 and UP9600
+	
+	// XXX provide implementation for both UP2400 and UP9600
+
+	jmp open_done_success
 
 
 #endif // HAS_RS232