/*---------Copyright (C) 1992 Dallas Semiconductor Corporation-------------- * * TOUCHIO2.C - C program module containing Low level I/O 1-Wire * functions for DALLAS Touch devices. * * 'setup' initializes the com port for use. * * 'TouchReset','TouchByte' and 'TouchBit' are Link-Level 1-Wire * routines. * * 'Finddevices','RomData'are Network-Level 1-Wire routines. * * 'crc16' and 'dowcrc' are cyclic redundancy routines. * * Compiler: Borland C++ Builder * */ #include #include #include #include #define FALSE 0 #define TRUE 1 #define SAMPLE_T 0xFE // Sampling at ~20uS #define DTR_ON 0x01 #define RTS_ON 0x02 #define DTR_RTS_ON 0x03 #define DTR_RTS_OFF 0x00 #define DATA_READY 0x01 unsigned char receive_zero_val; char *const com_poort[] = { " ", "COM1", "COM2", "COM3", "COM4", "COM5", "COM6", "COM7", "COM8" }; DCB dcb; /* External Variables declared in calling program */ extern int com_port; unsigned int CRC16; unsigned char DOWCRC; /* Function Prototypes */ int SetupPort( unsigned char ); int TouchByte( unsigned char ); int TouchReset( void ); int TouchBit(unsigned char); unsigned char FindDevices( void ); unsigned char * RomData( void ); unsigned int crc16(int); unsigned char dowcrc(unsigned char); void control_rts_dtr(); int read_rts_dtr(); unsigned char inportb(unsigned short int port); void outportb(unsigned short int port, unsigned char value); void CloseComport(); /* Global Variables for TOUCHIO.C */ HANDLE channel; unsigned char ROM[8]; unsigned char LD = 0; /* Last bit discrepancy in previous Next */ static unsigned char LastOne = 0; static unsigned char to_rts_dtr = 0; unsigned short int SPA; clock_t M; /*-------------------------------------------------------------------------- * The setup functions makes sure that the com port number passed to it * is from 1 to 8 and has a valid address associated with it. */ int SetupPort(unsigned char ComPort) { switch(ComPort) { case 1: SPA = 0x3F8; break; case 2: SPA = 0x2F8; break; case 3: SPA = 0x3E8; break; case 4: SPA = 0x2E8; break; case 5: SPA = 0x268; break; case 6: SPA = 0x3E0; break; case 7: SPA = 0x2E0; break; case 8: SPA = 0x260; break; } // check to see if it is a valid com port number and address if (ComPort < 1 || ComPort > 8 || !SPA ) return FALSE; channel = CreateFile(com_poort[ComPort], GENERIC_READ | GENERIC_WRITE, 0, // exclusive access NULL, // no security attrs OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, //FILE_FLAG_OVERLAPPED, NULL ); if(channel == INVALID_HANDLE_VALUE) { return false; // Deal with the error. } else { if(!GetCommState(channel, &dcb)) { CloseHandle(channel); return false; } } outportb((unsigned short)(SPA+3),0x87); // set DLAB outportb(SPA ,0x01); // bit rate is 115200 outportb((unsigned short)(SPA+3),0x07); // 8 dta, 2 stp, no par outportb((unsigned short)(SPA+1),0x00); // no interrupts control_rts_dtr(); return TRUE; } void control_rts_dtr() { to_rts_dtr = 0x03; outportb((unsigned short)(SPA+4),to_rts_dtr); } int read_rts_dtr() { return (int)inportb((unsigned short)(SPA+4)); } /*-------------------------------------------------------------------------- * Do a reset on the 1 wire port and return 0 no presence detect * 1 presence pulse no alarm * 2 alarm followed by a presence * 3 short circuit to ground * 4 no com port found * 5 timed out!! * The global variable 'com_port' must be set to the com port that * the serial brick is attached to before calling this routine. * */ int TouchReset( void ) { int X,Y,tmp,trst=1; M = clock() + 100; // Initialize the time limit 1mS steps while ((inportb(SPA+5) & DATA_READY) && (clock() <= M) ) { // Flush input X = inportb(SPA); } outportb((unsigned short)(SPA+3),0x83); // set DLAB outportb((unsigned short)(SPA+1),0x00); // baud rate is 9600 outportb(SPA,0x0C); // Low time is 5x104uS = 520uS outportb((unsigned short)(SPA+3),0x03); // 8 dta, 1 stp, no par outportb(SPA,0xF0); // send the reset pulse do // wait until character back or timeout { Y = inportb((unsigned short)(SPA+5)); } while( !(Y & DATA_READY) && (clock() <= M) ); if((Y & DATA_READY) && (Y != 0xFF)) X = inportb(SPA); else return 5; if (X != 0xF0) // if more bits back than sent then there is a { // device if framing error or break trst = 1; if ( (Y & 0x18) != 0 ) { trst = 2; do // loop to clear the buffers { tmp = inportb((unsigned short)(SPA+5)) & 0x60; } while ((tmp != 0x60) && (clock() <= M)); do // wait until character back or timeout { Y = inportb((unsigned short)(SPA+5)); } while ( !(Y & DATA_READY) && (clock() <= M) ); if (Y & DATA_READY) X = inportb(SPA); else return 3; } } else { trst = 0; } outportb((unsigned short)(SPA+3),0x87); // set DLAB outportb(SPA ,0x01); // 0x01 bit rate is 115200 outportb((unsigned short)(SPA+3),0x07); // 8 dta, 2 stp, no par return trst; } /*----------------------------------------------------------------------- * This is the 1-Wire routine 'TouchByte' or sometimes called 'databyte'. * It transmits 8 bits on to the 1-Wire data line and receives 8 bits * concurrently. The comport must be set to 115200 baud, 8 dta, 1 stp, * and no parity. This routine returns the unsigned char 8 bit value received. * If it times-out waiting for a character then -1 is returned. */ int TouchByte(unsigned char outchar) { unsigned char inchar=0,sendbit,Mask=1,receivebyte; M = clock() + 100; // Initialize the time limit do { if ( clock() > M ) // return if out of time return -1; } while ( (inportb((unsigned short)(SPA+5)) & 0x60) != 0x60 ); // wait to TBE and TSRE while ( (inportb((unsigned short)(SPA+5)) & DATA_READY) ) // flush input { inportb(SPA); if ( clock() > M ) // return if out of time return -1; } do // loop to send and receive 8 bits { sendbit = (outchar & Mask) ? 0xFF : 0x80; outportb(SPA,sendbit); // send out the bit Mask <<= 1; // get next bit ready to go out inchar >>= 1; // shift input char over ready for next bit for (;;) // loop to look for the incoming bit { if ( inportb((unsigned short)(SPA+5)) & DATA_READY ) { receivebyte = inportb(SPA); // the input byte if(receivebyte > SAMPLE_T) // Sample at 2,5 T inchar |= 0x80; else { if(receivebyte > 0xE0) receive_zero_val = receivebyte; inchar &= ~0x80; } break; // Byte received break for() loop } if ( clock() > M ) // return if out of time return -1; } } while (Mask); return inchar; // return the input char } /*-------------------------------------------------------------------------- * This is the 1-wire routine 'TouchBit'. It is used in the search rom * and match rom operations. It sends out one bit on the 1-wire and * returns one bit. The comport must be set to 115200 baud, 8 dta, 1 stp, * and no parity. If this routine times-out waiting for the bit character * then -1 is returned. */ int TouchBit(unsigned char outbit) { unsigned char sendbit,receivebit,receivebyte; M = clock() + 100; // Initialize the time limit do { if ( clock() > M ) // return if out of time return -1; } while ( (inportb((unsigned short)(SPA+5)) & 0x60) != 0x60 );// wait to TBE and TSRE while ( (inportb((unsigned short)(SPA+5)) & DATA_READY) ) // flush input { inportb(SPA); if ( clock() > M ) // return if out of time return -1; } sendbit = (outbit & 0x1) ? 0xFF : 0x80; // get bit ready to go out outportb(SPA,sendbit); // send out the bit for (;;) // loop to look for the incoming bit { if( inportb((unsigned short)(SPA+5)) & DATA_READY ) { receivebyte = inportb(SPA); // return the input byte if(receivebyte > SAMPLE_T) // Sample at 2,5 T receivebit = 1; else { receivebit = 0; } return (receivebit); } if( clock() > M ) // return if out of time return -1; } } /*-------------------------------------------------------------------------- * This function searchs for the next device on the 1-wire. */ unsigned char FindDevices( void ) { unsigned char Bit=1,Byte=0,Mask=1,LO=0,G,NXT; unsigned char ROMNEW[8]; int i, x; int tries; NXT = FALSE; // set the next flag to false DOWCRC = 0; // reset the DOWCRC // if the last call was not the last one tries = 0; // bij een storing probeer een aantal keren if (!LastOne) { Storing: Bit=1;Byte=0;Mask=1;LO=0;DOWCRC=0;NXT=FALSE; x = TouchReset(); // reset the 1-wire if ((x == 0 || x == 5)) { // if there are no parts or alarming parts on 1-wire, return FL LD = 0; // reset the search return FALSE; } // TouchReset(); // reset the 1-wire // TouchReset(); // reset the 1-wire if(TouchByte(0xF0) == -1) // issue the search rom command { goto Storing; } do // loop to do the search rom at the bus { x = TouchBit(1) << 1; // read a bit and its compliment x |= TouchBit(1); if (x == 3) // there are no devices on 1-wire { if(tries++ > 20) break; // Teveel storing else goto Storing; } else { if (x > 0) // all devices coupled have 0 or 1 G = !(x & 0x01); // bit write value for search else { // if this discrepancy if before the Last Discrepancy // on a previous next then pick the same as last time if (Bit < LD) G = ((ROM[Byte] & Mask) > 0); else // if equal to last pick 1 G = (Bit == LD);// if not then pick 0 // if 0 was picked then record its position in LO if (G == 0) LO = Bit; } if (G == 1) // set or clear the bit in the ROM byte J with mask K ROMNEW[Byte] |= Mask; else ROMNEW[Byte] &= ~Mask; G = TouchBit(G); // rom search write Bit++; // increment the byte counter I and shift the mask K Mask = Mask << 1; if (Mask == 0) // if the mask is 0 then go to new ROM byte J and reset mask { dowcrc(ROMNEW[Byte]); // accumulate the CRC Byte++; // Next byte in the ROM-code Mask = 1; // Mask byte } } } while(Byte < 8); // loop until through all ROM bytes 0-7 if (Bit < 65 || DOWCRC) // if the search was unsuccessful then LD = 0; // reset the Last Discrepancy to 0 else { // search successful to set LD,LastOne,NXT LD = LO; LastOne = (LD == 0); NXT = TRUE; for(i=0;i<8;i++) ROM[i] = ROMNEW[i]; // ROM[x] is used by the program } } // if no device found then reset counters so next 'next' will be // like a first if (!NXT) { LD = 0; LastOne = FALSE; } return NXT; } // The folowing routine access some resources directly // it only works under WINDOWS 95 / 98, not under NT!! // It returns from a given port-address a value unsigned char inportb(unsigned short int port) { unsigned char value; __emit__(0x8b, 0x95, &port); __emit__(0x66, 0xec); __emit__(0x88, 0x85, &value); return value; } // The folowing routine access some resources directly // it only works under WINDOWS 95 / 98, not under NT!! // It gives a port-address a value void outportb(unsigned short int port, unsigned char value) { __emit__(0x8b, 0x95, &port); __emit__(0x8a, 0x85, &value); __emit__(0x66, 0xee); } void CloseComport() { CloseHandle(channel); } /*-------------------------------------------------------------------------- * The 'RomData' function returns the pointer to the ROM DATA. */ unsigned char * RomData( void ) { return &ROM[0]; } /*-------------------------------------------------------------------------- * Calculate a new CRC16 from the input data integer. Return the current * CRC16 and also update the global variable CRC16. */ static int oddparity[16] = { 0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0 }; unsigned int crc16(int data) { data = (data ^ (CRC16 & 0xff)) & 0xff; CRC16 >>= 8; if (oddparity[data & 0xf] ^ oddparity[data >> 4]) CRC16 ^= 0xc001; data <<= 6; CRC16 ^= data; data <<= 1; CRC16 ^= data; return CRC16; } unsigned char dscrc_table[] = { 0, 94,188,226, 97, 63,221,131,194,156,126, 32,163,253, 31, 65, 157,195, 33,127,252,162, 64, 30, 95, 1,227,189, 62, 96,130,220, 35,125,159,193, 66, 28,254,160,225,191, 93, 3,128,222, 60, 98, 190,224, 2, 92,223,129, 99, 61,124, 34,192,158, 29, 67,161,255, 70, 24,250,164, 39,121,155,197,132,218, 56,102,229,187, 89, 7, 219,133,103, 57,186,228, 6, 88, 25, 71,165,251,120, 38,196,154, 101, 59,217,135, 4, 90,184,230,167,249, 27, 69,198,152,122, 36, 248,166, 68, 26,153,199, 37,123, 58,100,134,216, 91, 5,231,185, 140,210, 48,110,237,179, 81, 15, 78, 16,242,172, 47,113,147,205, 17, 79,173,243,112, 46,204,146,211,141,111, 49,178,236, 14, 80, 175,241, 19, 77,206,144,114, 44,109, 51,209,143, 12, 82,176,238, 50,108,142,208, 83, 13,239,177,240,174, 76, 18,145,207, 45,115, 202,148,118, 40,171,245, 23, 73, 8, 86,180,234,105, 55,213,139, 87, 9,235,181, 54,104,138,212,149,203, 41,119,244,170, 72, 22, 233,183, 85, 11,136,214, 52,106, 43,117,151,201, 74, 20,246,168, 116, 42,200,150, 21, 75,169,247,182,232, 10, 84,215,137,107, 53}; /*-------------------------------------------------------------------------- * Update the Dallas Semiconductor One Wire CRC (DOWCRC) from the global * variable DOWCRC and the argument. Return the updated DOWCRC. */ unsigned char dowcrc(unsigned char x) { DOWCRC = dscrc_table[DOWCRC ^ x]; return DOWCRC; }