File content as of revision 1:dcf2f8359398:
//---------------------------------------------------------------------------
// Copyright (C) 2000v Dallas Semiconductor Corporation, All Rights Reserved.
//
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// Software is furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included
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// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
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// IN NO EVENT SHALL DALLAS SEMICONDUCTOR BE LIABLE FOR ANY CLAIM, DAMAGES
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// 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.
//---------------------------------------------------------------------------
//
// ds2480ut.c - DS2480B utility functions.
//
// Version: 2.01
//
// History: 1.00 -> 1.01 Default PDSRC changed from 0.83 to 1.37V/us
// in DS2480Detect. Changed to use msDelay instead
// of Delay.
// 1.01 -> 1.02 Changed global declarations from 'uchar' to 'int'.
// Changed DSO/WORT from 7 to 10us in DS2480Detect.
// 1.02 -> 1.03 Removed caps in #includes for Linux capatibility
// 1.03 -> 2.00 Changed 'MLan' to 'ow'. Added support for
// multiple ports. Changed W1LT to 8us.
// 2.00 -> 2.01 Added error handling. Added circular-include check.
// 2.01 -> 2.10 Added raw memory error handling and SMALLINT
// 2.10 -> 3.00 Added memory bank functionality
// Added file I/O operations
//
#include "ownet.h"
#include "./Headers/ds2480.h"
// global DS2480B state
SMALLINT ULevel[MAX_PORTNUM]; // current DS2480B 1-Wire Net level
SMALLINT UBaud[MAX_PORTNUM]; // current DS2480B baud rate
SMALLINT UMode[MAX_PORTNUM]; // current DS2480B command or data mode state
SMALLINT USpeed[MAX_PORTNUM]; // current DS2480B 1-Wire Net communication speed
SMALLINT UVersion[MAX_PORTNUM]; // current DS2480B version
//---------------------------------------------------------------------------
// Attempt to resyc and detect a DS2480B
//
// 'portnum' - number 0 to MAX_PORTNUM-1. This number was provided to
// OpenCOM to indicate the port number.
//
// Returns: TRUE - DS2480B detected successfully
// FALSE - Could not detect DS2480B
//
SMALLINT DS2480Detect(int portnum)
{
uchar sendpacket[10],readbuffer[10];
uchar sendlen=0;
// reset modes
UMode[portnum] = MODSEL_COMMAND;
UBaud[portnum] = PARMSET_INV_9600;
USpeed[portnum] = SPEEDSEL_FLEX;
// set the baud rate to 9600
SetBaudCOM(portnum,(uchar)UBaud[portnum]);
// send a break to reset the DS2480
BreakCOM(portnum);
// delay to let line settle
msDelay(2);
// flush the buffers
FlushCOM(portnum);
// send the reset byte
sendpacket[0] = 0xC1;
if (WriteCOM(portnum,1,sendpacket) != 1)
{
OWERROR(OWERROR_WRITECOM_FAILED);
return FALSE;
}
// delay to let line settle
msDelay(4);
// send the Baud Rate byte, which also inverts RX signal
sendpacket[0] = 0x79;
if (WriteCOM(portnum,1,sendpacket) != 1)
{
OWERROR(OWERROR_WRITECOM_FAILED);
return FALSE;
}
// delay to let line settle
msDelay(4);
// set the FLEX configuration parameters
// default PDSRC = 1.37Vus
sendpacket[sendlen++] = CMD_CONFIG | PARMSEL_SLEW | PARMSET_Slew1p37Vus;
// default W1LT = 10us
sendpacket[sendlen++] = CMD_CONFIG | PARMSEL_WRITE1LOW | PARMSET_Write10us;
// default DSO/WORT = 8us
sendpacket[sendlen++] = CMD_CONFIG | PARMSEL_SAMPLEOFFSET | PARMSET_SampOff8us;
// construct the command to read the baud rate (to test command block)
sendpacket[sendlen++] = CMD_CONFIG | PARMSEL_PARMREAD | (PARMSEL_BAUDRATE >> 3);
// also do 1 bit operation (to test 1-Wire block)
sendpacket[sendlen++] = CMD_COMM | FUNCTSEL_BIT | UBaud[portnum] | BITPOL_ONE;
// flush the buffers
FlushCOM(portnum);
// send the packet
if (WriteCOM(portnum,sendlen,sendpacket))
{
// read back the response
if (ReadCOM(portnum,5,readbuffer) == 5)
{
// look at the baud rate and bit operation
// to see if the response makes sense
if (((readbuffer[3] & 0xF1) == 0x00) &&
((readbuffer[3] & 0x0E) == UBaud[portnum]) &&
((readbuffer[4] & 0xF0) == 0x90) &&
((readbuffer[4] & 0x0C) == UBaud[portnum]))
return TRUE;
else
OWERROR(OWERROR_DS2480_BAD_RESPONSE);
}
else
OWERROR(OWERROR_READCOM_FAILED);
}
else
OWERROR(OWERROR_WRITECOM_FAILED);
return FALSE;
}
//---------------------------------------------------------------------------
// Change the DS2480B from the current baud rate to the new baud rate.
//
// 'portnum' - number 0 to MAX_PORTNUM-1. This number was provided to
// OpenCOM to indicate the port number.
// 'newbaud' - the new baud rate to change to, defined as:
// PARMSET_9600 0x00
// PARMSET_19200 0x02
// PARMSET_57600 0x04
// PARMSET_115200 0x06
//
// Returns: current DS2480B baud rate.
//
SMALLINT DS2480ChangeBaud(int portnum, uchar newbaud)
{
uchar rt=FALSE;
uchar readbuffer[5],sendpacket[5],sendpacket2[5];
uchar sendlen=0,sendlen2=0;
// see if diffenent then current baud rate
if (UBaud[portnum] == newbaud)
return UBaud[portnum];
else
{
// build the command packet
// check if correct mode
if (UMode[portnum] != MODSEL_COMMAND)
{
UMode[portnum] = MODSEL_COMMAND;
sendpacket[sendlen++] = MODE_COMMAND;
}
// build the command
sendpacket[sendlen++] = CMD_CONFIG | PARMSEL_BAUDRATE | newbaud;
// flush the buffers
FlushCOM(portnum);
// send the packet
if (!WriteCOM(portnum,sendlen,sendpacket))
{
OWERROR(OWERROR_WRITECOM_FAILED);
rt = FALSE;
}
else
{
// make sure buffer is flushed
msDelay(5);
// change our baud rate
SetBaudCOM(portnum,newbaud);
UBaud[portnum] = newbaud;
// wait for things to settle
msDelay(5);
// build a command packet to read back baud rate
sendpacket2[sendlen2++] = CMD_CONFIG | PARMSEL_PARMREAD | (PARMSEL_BAUDRATE >> 3);
// flush the buffers
FlushCOM(portnum);
// send the packet
if (WriteCOM(portnum,sendlen2,sendpacket2))
{
// read back the 1 byte response
if (ReadCOM(portnum,1,readbuffer) == 1)
{
// verify correct baud
if (((readbuffer[0] & 0x0E) == (sendpacket[sendlen-1] & 0x0E)))
rt = TRUE;
else
OWERROR(OWERROR_DS2480_WRONG_BAUD);
}
else
OWERROR(OWERROR_READCOM_FAILED);
}
else
OWERROR(OWERROR_WRITECOM_FAILED);
}
}
// if lost communication with DS2480 then reset
if (rt != TRUE)
DS2480Detect(portnum);
return UBaud[portnum];
}
Steven Vlach