diff --git a/olimexino-stm32/olimexino_stm32.ft b/olimexino-stm32/olimexino_stm32.ft
index fa4697b..5abde9b 100644
--- a/olimexino-stm32/olimexino_stm32.ft
+++ b/olimexino-stm32/olimexino_stm32.ft
@@ -396,15 +396,18 @@ VARIABLE EP0-REQ-LENGTH
 
 : IN-HANDLER ( ep dir -- )
     DROP DUP EP-CLEAR-CTR-TX
-    CON-TX# IF DUP CON-TX>PMA 3 SWAP EP-TX-STATE! ELSE DROP THEN
+    CON-TX# IF DUP CON-TX>PMA 3 SWAP EP-TX-STATE! ELSE USB-BTABLE-TX# 0 SWAP ! THEN
     ;
 
 : USB-TX ( c-addr n -- )
     BEGIN ?DUP WHILE OVER C@ CON-TX! 1- SWAP 1+ SWAP REPEAT DROP
-    3 1 EP-TX-STATE!
+    USB-EP1R @ 0030 AND 3 <> IF 3 1 EP-TX-STATE! THEN
     ;
 
-: USB-EMIT ( c -- ) CON-TX! 3 1 EP-TX-STATE! ;
+: USB-EMIT ( c -- )
+    CON-TX!
+    USB-EP1R @ 0030 AND 3 <> IF 3 1 EP-TX-STATE! THEN
+    ;
 
 : USB
     1 USB-DISC! USB-INIT