anchor.diff:  function USB_EP0StartXfer(var USBx: USB_OTG_GlobalTypeDef; var ep: USB_OTG_EPTypeDef; dma: boolean): HAL_StatusTypeDef;
   begin
     (* IN endpoint *)
  -  if (ep.is_in = 1) then
  +  if (ep.is_in) then
     begin
       (* Zero Length Packet? *)
       if (ep.xfer_len = 0) then
  
positive.code:   //debug := 0;
  
    (* Read DEPCTLn register *)
    if (ep.is_in = 1) then
    begin
      if (((USBx_INEP(usbx,ep.num)^.DIEPCTL) and USB_OTG_DIEPCTL_USBAEP) = 0) then
      begin
  
negative.code:     end;
  
      if (dma) then
        USBx_INEP(usbx,ep.num)^.DIEPDMA := longword(ep.dma_addr)
      else
      begin
        if (ep.type_ <> EP_TYPE_ISOC) then
  