fixed the receive 0 bytes bug, where full buffers block the usb port and never get re-enabled.

1 files changed, 8 insertions, 0 deletions

diff --git a/core/usb/usb.c b/core/usb/usb.c
index cb8de52..a8298c0 100644
--- a/core/usb/usb.c
+++ b/core/usb/usb.c
@@ -407,6 +407,12 @@ uint8 usbReceiveBytes(uint8* recvBuf, uint8 len) {
   }
 
   maxNewBytes += len;
+
+  /* re-enable the rx endpoint which we had set to receive 0 bytes */
+  if (maxNewBytes - len == 0) {
+    SetEPRxCount(VCOM_RX_ENDP,maxNewBytes);
+  }
+
   return len;
 }
 
@@ -415,10 +421,12 @@ void usbSendHello(void) {
 
   uint8 bufin = 48 + recvBufIn;;
   uint8 bufout = 48 + recvBufOut;
+  uint8 avail  = 48 + usbBytesAvailable();
 
   char *line = "\r\n";
   while(usbSendBytes(&bufin,1) == 0);
   while(usbSendBytes(&bufout,1) == 0);
+  while(usbSendBytes(&avail,1) == 0);
   while(usbSendBytes((uint8*)line,2) == 0);
 
   uint8 recv[64];