/*----------------------------------------------------------------------
* Read the switch information byte.
*/
short ReadSwitchInfo(long session_handle, short ClearActivity)
{
short flag,rt=-1;
unsigned char CRCByte;
/* access and verify it is there */
flag = TMAccess(session_handle,&state_buffer);
if (flag == 1)
{
/* reset CRC */
CRC16 = 0;
/* channel access command */
flag = TMTouchByte(session_handle,0xF5);
CRCByte = 0xF5;
CRC16 = TMCRC(1, &CRCByte, (ushort)CRC16, 1);
/* control bytes */
if (ClearActivity)
{
TMTouchByte(session_handle,0xD5);
CRCByte = 0xD5;
CRC16 = TMCRC(1, &CRCByte, (ushort)CRC16, 1);
}
else
{
TMTouchByte(session_handle,0x55);
CRCByte = 0x55;
CRC16 = TMCRC(1, &CRCByte, (ushort)CRC16, 1);
}
TMTouchByte(session_handle,0xFF);
CRCByte = 0xFF;
CRC16 = TMCRC(1, &CRCByte, (ushort)CRC16, 1);
/* read the info byte */
rt = TMTouchByte(session_handle,0xFF);
CRCByte = (unsigned char) rt;
CRC16 = TMCRC(1, &CRCByte, (ushort)CRC16, 1);
/* read a dummy read byte and CRC16 */
CRCByte = (unsigned char) TMTouchByte(session_handle,0xFF);
CRC16 = TMCRC(1, &CRCByte, (ushort)CRC16, 1);
CRCByte = (unsigned char) TMTouchByte(session_handle,0xFF);
CRC16 = TMCRC(1, &CRCByte, (ushort)CRC16, 1);
CRCByte = (unsigned char) TMTouchByte(session_handle,0xFF);
CRC16 = TMCRC(1, &CRCByte, (ushort)CRC16, 1);
/* check result */
if (CRC16 != 0xB001)
rt = -1;
}
else
rt = -1;
return rt;
}
//--------------------------------------------------------------------------
// The 'owAccess' function resets the 1-Wire and sends a MATCH Serial
// Number command followed by the current SerialNum code. After this
// function is complete the 1-Wire device is ready to accept device-specific
// commands.
//
// 'portnum' - number 0 to MAX_PORTNUM-1. This number is provided to
// indicate the symbolic port number.
//
// Returns: TRUE (1) : reset indicates present and device is ready
// for commands.
// FALSE (0): reset does not indicate presence or echos 'writes'
// are not correct.
//
SMALLINT owAccess(int portnum)
{
return (TMAccess(SessionHandle[portnum], StateBuffer[portnum]) == 1);
}
/*----------------------------------------------------------------------
* Set the flip flops to the 'ffstate' .
*/
short SetFlipFlop(short ffstate)
{
short printmsg=1,flag,rt=0,cnt=0,done=0;
long session_handle;
unsigned char CRCByte;
// loop to get a session handle and to a temperature conversion */
do
{
/* attempt to get a session */
session_handle = TMExtendedStartSession(PortNum,PortType,NULL);
if (session_handle > 0)
{
/* access and verify it is there */
if (TMAccess(session_handle,&state_buffer) == 1)
{
/* reset CRC */
CRC16 = 0;
/* write status command */
flag = TMTouchByte(session_handle,0x55);
CRCByte = 0x55;
CRC16 = TMCRC(1, &CRCByte, 0, 1);
/* send address */
TMTouchByte(session_handle,0x07);
CRCByte = 0x07;
CRC16 = TMCRC(1, &CRCByte, (ushort)CRC16, 1);
TMTouchByte(session_handle,0x00);
CRCByte = 0x00;
CRC16 = TMCRC(1, &CRCByte, (ushort)CRC16, 1);
/* write that status */
TMTouchByte(session_handle,ffstate);
CRCByte = (unsigned char) ffstate;
CRC16 = TMCRC(1, &CRCByte, (ushort)CRC16, 1);
/* crc */
flag = TMTouchByte(session_handle, 0xFF);
CRCByte = (unsigned char) flag;
CRC16 = TMCRC(1, &CRCByte, (ushort)CRC16, 1);
flag = TMTouchByte(session_handle, 0xFF);
CRCByte = (unsigned char) flag;
CRC16 = TMCRC(1, &CRCByte, (ushort)CRC16, 1);
/* check result */
if (CRC16 == 0xB001)
done = TRUE;
else
cnt++;
}
/* end the session if one is open */
TMEndSession(session_handle);
}
else if (session_handle == 0)
{
/* check if need to print the waiting message */
if (printmsg)
{
printmsg = FALSE;
printf("\nWaiting to get access to the 1-Wire network\n\n");
}
}
}
while (!done && (cnt < 10));
return done;
}
