diff --git a/bin/basic_generic.rom b/bin/basic_generic.rom
index 51ee2980..71a7c830 100644
Binary files a/bin/basic_generic.rom and b/bin/basic_generic.rom differ
diff --git a/bin/basic_mega65.rom b/bin/basic_mega65.rom
index 84c54593..17939d89 100644
Binary files a/bin/basic_mega65.rom and b/bin/basic_mega65.rom differ
diff --git a/bin/basic_ultimate64.rom b/bin/basic_ultimate64.rom
index 5df8a636..0d1f0cef 100644
Binary files a/bin/basic_ultimate64.rom and b/bin/basic_ultimate64.rom differ
diff --git a/bin/kernal_generic.rom b/bin/kernal_generic.rom
index a1e4bfcf..8085094a 100644
Binary files a/bin/kernal_generic.rom and b/bin/kernal_generic.rom differ
diff --git a/bin/kernal_mega65.rom b/bin/kernal_mega65.rom
index a1e4bfcf..8085094a 100644
Binary files a/bin/kernal_mega65.rom and b/bin/kernal_mega65.rom differ
diff --git a/bin/kernal_ultimate64.rom b/bin/kernal_ultimate64.rom
index a1e4bfcf..8085094a 100644
Binary files a/bin/kernal_ultimate64.rom and b/bin/kernal_ultimate64.rom differ
diff --git a/c64/kernal/f34a.open.s b/c64/kernal/f34a.open.s
index c1bbb282..81192de3 100644
--- a/c64/kernal/f34a.open.s
+++ b/c64/kernal/f34a.open.s
@@ -21,7 +21,9 @@ open:
 	dey
 	lda LAT, y
 	cmp current_logical_filenum
-	beq kernalerror_FILE_ALREADY_OPEN
+	bne open_not_yet_open
+	jmp kernalerror_FILE_ALREADY_OPEN
+open_not_yet_open:
 	cpy #$00
 	jmp -
 *
diff --git a/c64/kernal/iec/iec_tx_byte.s b/c64/kernal/iec/iec_tx_byte.s
index 5f24b6c7..76c12e45 100644
--- a/c64/kernal/iec/iec_tx_byte.s
+++ b/c64/kernal/iec/iec_tx_byte.s
@@ -90,6 +90,7 @@ iec_tx_common_bit_is_sent:
 	bpl +
 	dex
 	bne -
-	bpl iec_return_DEVICE_NOT_FOUND
+	bmi +
+	jmp iec_return_DEVICE_NOT_FOUND
 *
 	jmp iec_return_success