diff --git a/atusb/fw/usb/atu2.c b/atusb/fw/usb/atu2.c
index abb6de8..d587983 100644
--- a/atusb/fw/usb/atu2.c
+++ b/atusb/fw/usb/atu2.c
@@ -70,6 +70,15 @@ int set_addr(uint8_t addr)
 }
 
 
+void usb_ep_change(struct ep_descr *ep)
+{
+	if (ep->state == EP_TX) {
+		UENUM = ep-eps;
+		UEIENX |= 1 << TXINE;
+	}
+}
+
+
 static int ep_setup(void)
 {
 	struct setup_request setup;
@@ -157,6 +166,8 @@ static void handle_ep(int n)
 			UEINTX = ~(1 << TXINI);
 			if (ep->state == EP_IDLE && ep->callback)
 				ep->callback(ep->user);
+		} else {
+			UEIENX &= ~(1 << TXINE);
 		}
 	}
 	return;
diff --git a/atusb/fw/usb/usb.c b/atusb/fw/usb/usb.c
index 8239735..afed4c6 100644
--- a/atusb/fw/usb/usb.c
+++ b/atusb/fw/usb/usb.c
@@ -51,6 +51,7 @@ void usb_io(struct ep_descr *ep, enum ep_state state, uint8_t *buf,
 	ep->end = buf+size;
 	ep->callback = callback;
 	ep->user = user;
+	usb_ep_change(ep);
 }
 
 
diff --git a/atusb/fw/usb/usb.h b/atusb/fw/usb/usb.h
index f6e7655..f508091 100644
--- a/atusb/fw/usb/usb.h
+++ b/atusb/fw/usb/usb.h
@@ -150,6 +150,7 @@ void usb_io(struct ep_descr *ep, enum ep_state state, uint8_t *buf,
 
 int handle_setup(const struct setup_request *setup);
 int set_addr(uint8_t addr);
+void usb_ep_change(struct ep_descr *ep);
 void usb_reset(void);
 void usb_init(void);