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Diffstat (limited to 'src/pmdas/roomtemp/mlan/ds2480ut.c')
| -rw-r--r-- | src/pmdas/roomtemp/mlan/ds2480ut.c | 206 |
1 files changed, 206 insertions, 0 deletions
diff --git a/src/pmdas/roomtemp/mlan/ds2480ut.c b/src/pmdas/roomtemp/mlan/ds2480ut.c new file mode 100644 index 0000000..d353743 --- /dev/null +++ b/src/pmdas/roomtemp/mlan/ds2480ut.c @@ -0,0 +1,206 @@ +//--------------------------------------------------------------------------- +// Copyright (C) 1999 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. +//--------------------------------------------------------------------------- +// +// ds2480ut.c - DS2480 utility functions. +// +// Version: 1.03 +// +// 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 + +#include "ds2480.h" +#include "mlan.h" + +// external COM functions required +extern void FlushCOM(void); +extern int WriteCOM(int, uchar *); +extern int ReadCOM(int, uchar *); +extern void BreakCOM(void); +//extern void SetBaudCOM(uchar); +extern void msDelay(int); + +// exportable functions +int DS2480Detect(void); +int DS2480ChangeBaud(uchar); + +// global DS2480 state +int UMode = MODSEL_COMMAND; // current DS2480 command or data mode stateuchar +int UBaud = PARMSET_9600; // current DS2480 baud rate +int USpeed = SPEEDSEL_FLEX; // current DS2480 MicroLAN communication speed +int ULevel = MODE_NORMAL; // current DS2480 MicroLAN level + +//--------------------------------------------------------------------------- +// Attempt to resyc and detect a DS2480 +// +// Returns: TRUE - DS2480 detected successfully +// FALSE - Could not detect DS2480 +// +int DS2480Detect(void) +{ + uchar sendpacket[10],readbuffer[10]; + short sendlen=0; + + // reset modes + UMode = MODSEL_COMMAND; + UBaud = PARMSET_9600; + USpeed = SPEEDSEL_FLEX; + + // set the baud rate to 9600 + SetBaudCOM((uchar)UBaud); + + // send a break to reset the DS2480 + BreakCOM(); + + // delay to let line settle + msDelay(2); + + // flush the buffers + FlushCOM(); + + // send the timing byte + sendpacket[0] = 0xC1; + if (WriteCOM(1,sendpacket) != 1) + return FALSE; + + // set the FLEX configuration parameters + // default PDSRC = 1.37Vus + sendpacket[sendlen++] = CMD_CONFIG | PARMSEL_SLEW | PARMSET_Slew1p37Vus; + // default W1LT = 12us + sendpacket[sendlen++] = CMD_CONFIG | PARMSEL_WRITE1LOW | PARMSET_Write12us; + // default DSO/WORT = 10us + sendpacket[sendlen++] = CMD_CONFIG | PARMSEL_SAMPLEOFFSET | PARMSET_SampOff10us; + + // 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 | BITPOL_ONE; + + // flush the buffers + FlushCOM(); + + // send the packet + if (WriteCOM(sendlen,sendpacket)) + { + // read back the response + if (ReadCOM(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) && + ((readbuffer[4] & 0xF0) == 0x90) && + ((readbuffer[4] & 0x0C) == UBaud)) + return TRUE; + } + } + + return FALSE; +} + + +//--------------------------------------------------------------------------- +// Change the DS2480 from the current baud rate to the new baud rate. +// +// 'newbaud' - the new baud rate to change to, defined as: +// PARMSET_9600 0x00 +// PARMSET_19200 0x02 +// PARMSET_57600 0x04 +// PARMSET_115200 0x06 +// +// Returns: current DS2480 baud rate. +// +int DS2480ChangeBaud(uchar newbaud) +{ + int rt=FALSE; + uchar readbuffer[5],sendpacket[5],sendpacket2[5]; + int sendlen=0,sendlen2=0; + + // see if diffenent then current baud rate + if (UBaud == newbaud) + return TRUE; + else + { + // build the command packet + // check if correct mode + if (UMode != MODSEL_COMMAND) + { + UMode = MODSEL_COMMAND; + sendpacket[sendlen++] = MODE_COMMAND; + } + // build the command + sendpacket[sendlen++] = CMD_CONFIG | PARMSEL_BAUDRATE | newbaud; + + // flush the buffers + FlushCOM(); + + // send the packet + if (!WriteCOM(sendlen,sendpacket)) + rt = FALSE; + else + { + // make sure buffer is flushed + msDelay(5); + + // change our baud rate + SetBaudCOM(newbaud); + UBaud = 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(); + + // send the packet + if (WriteCOM(sendlen2,sendpacket2)) + { + // read back the 1 byte response + if (ReadCOM(1,readbuffer) == 1) + { + // verify correct baud + if (((readbuffer[0] & 0x0E) == (sendpacket[sendlen-1] & 0x0E))) + rt = TRUE; + } + } + } + } + + // if lost communication with DS2480 then reset + if (rt != TRUE) + DS2480Detect(); + + return UBaud; +} |