📄 usbwses.c
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//---------------------------------------------------------------------------
// Copyright (C) 2003 Dallas Semiconductor Corporation, All Rights Reserved.
//
// Permission is hereby granted, free of charge, to any person obtaining a
// copy of this software and associated documentation files (the "Software"),
// to deal in the Software without restriction, including without limitation
// the rights to use, copy, modify, merge, publish, distribute, sublicense,
// and/or sell copies of the Software, and to permit persons to whom the
// Software is furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included
// in all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
// IN NO EVENT SHALL DALLAS SEMICONDUCTOR BE LIABLE FOR ANY CLAIM, DAMAGES
// OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
// ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
// OTHER DEALINGS IN THE SOFTWARE.
//
// Except as contained in this notice, the name of Dallas Semiconductor
// shall not be used except as stated in the Dallas Semiconductor
// Branding Policy.
//---------------------------------------------------------------------------
//
// usbwses.c - Acquire and release a Session on the 1-Wire Net using the
// USB interface DS2490.
//
// Version: 3.00
//
// History:
//
#include "ownet.h"
#include "ds2490.h"
// handles to USB ports
HANDLE usbhnd[MAX_PORTNUM];
static SMALLINT usbhnd_init = 0;
//---------------------------------------------------------------------------
// Attempt to acquire a 1-Wire net using a USB port and a DS2490 based
// adapter.
//
// 'portnum' - number 0 to MAX_PORTNUM-1. This number is provided to
// indicate the symbolic port number.
// 'port_zstr' - zero terminated port name. For this platform
// use format '\\.\DS2490-X' where X is the port number.
//
// Returns: TRUE - success, COM port opened
//
SMALLINT owAcquire(int portnum, char *port_zstr)
{
if(!usbhnd_init)
{
int i;
for(i=0; i<MAX_PORTNUM; i++)
usbhnd[0] = 0;
usbhnd_init = 1;
}
OWASSERT( portnum<MAX_PORTNUM && portnum>=0 && !usbhnd[portnum],
OWERROR_PORTNUM_ERROR, FALSE );
// get a handle to the device
usbhnd[portnum] = CreateFile(port_zstr,
GENERIC_READ | GENERIC_WRITE,
FILE_SHARE_READ,
NULL,
OPEN_EXISTING,
FILE_ATTRIBUTE_NORMAL,
NULL);
if (usbhnd[portnum] != INVALID_HANDLE_VALUE)
{
// verify adapter is working
if (!AdapterRecover(portnum))
{
CloseHandle(usbhnd[portnum]);
return FALSE;
}
// reset the 1-Wire
owTouchReset(portnum);
}
else
{
// could not get resouse
OWERROR(OWERROR_GET_SYSTEM_RESOURCE_FAILED);
return FALSE;
}
return TRUE;
}
//---------------------------------------------------------------------------
// Attempt to acquire the specified 1-Wire net.
//
// 'port_zstr' - zero terminated port name.
//
// Returns: port number or -1 if not successful in setting up the port.
//
int owAcquireEx(char *port_zstr)
{
int portnum = 0;
if(!usbhnd_init)
{
int i;
for(i=0; i<MAX_PORTNUM; i++)
usbhnd[0] = 0;
usbhnd_init = 1;
}
// check to find first available handle slot
for(portnum = 0; portnum<MAX_PORTNUM; portnum++)
{
if(!usbhnd[portnum])
break;
}
OWASSERT( portnum<MAX_PORTNUM, OWERROR_PORTNUM_ERROR, -1 );
// get a handle to the device
usbhnd[portnum] = CreateFile(port_zstr,
GENERIC_READ | GENERIC_WRITE,
FILE_SHARE_READ,
NULL,
OPEN_EXISTING,
FILE_ATTRIBUTE_NORMAL,
NULL);
if (usbhnd[portnum] != INVALID_HANDLE_VALUE)
{
// verify adapter is working
if (!AdapterRecover(portnum))
{
CloseHandle(usbhnd[portnum]);
return -1;
}
// reset the 1-Wire
owTouchReset(portnum);
}
else
{
// could not get resouse
OWERROR(OWERROR_GET_SYSTEM_RESOURCE_FAILED);
return -1;
}
return portnum;
}
//---------------------------------------------------------------------------
// Release the port previously acquired a 1-Wire net.
//
// 'portnum' - number 0 to MAX_PORTNUM-1. This number is provided to
// indicate the symbolic port number.
//
void owRelease(int portnum)
{
CloseHandle(usbhnd[portnum]);
}
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