# HG changeset patch # User darius # Date 1145798836 -34200 # Node ID b0cb873c0206edaa755e51028abf764baaf9c8c2 # Parent 4e417d84365e7d1c204f8ca8db9440aee23000cc Isolate the bus frobbing parts and the delays into a separate header. This means the user only has to edit a single file to suit their situation and allows the code to work with active drive systems as well as passive pullups (ie 1 vs 2 IO pins) diff -r 4e417d84365e -r b0cb873c0206 1wire-config.h --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/1wire-config.h Sun Apr 23 22:57:16 2006 +0930 @@ -0,0 +1,72 @@ +/* + * 1 wire header + * + * This is the user servicable stuff - how to do delays and how to + * frob the IO pins. + * + * $Id$ + * + * Copyright (c) 2004 + * Daniel O'Connor . All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY AUTHOR AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + */ + +/* + * Alter these for your configuration + */ + +/* Set DDR on the right pins */ +#define OWBUSINIT() do { \ + DDRD |= _BV(4); \ + DDRD &= ~_BV(3); \ + } while (0) + +/* Read the 1-wire bus, non-inverting logic */ +#define OWREADBUS() (PIND & _BV(3) ? 1 : 0) + +/* Set the 1-wire bus to 0 + * Turns a transistor on to pull it low + */ +#define OWSETBUSLOW() PORTD |= _BV(4) + +/* Set the 1-wire bus to 1 + * Turn the transistor off to let the pullup do its job + */ +#define OWSETBUSHIGH() PORTD &= ~_BV(4) + +/* _delay_us can only do a delay of 768/clock_freq */ +#if F_CPU > 16000000 +#error F_CPU > 16MHz, delays need adjusting +#endif + +#define OWDELAY_A _delay_us(6) /* 6 usec */ +#define OWDELAY_B do { _delay_us(48); _delay_us(16); } while (0) /* 64 usec */ +#define OWDELAY_C do { _delay_us(48); _delay_us(12); } while (0) /* 60 usec */ +#define OWDELAY_D _delay_us(10) /* 10 usec */ +#define OWDELAY_E _delay_us(9) /* 9 usec */ +#define OWDELAY_F do { _delay_us(55); } while (0) /* 55 usec */ +#define OWDELAY_G /* 0 usec */ +#define OWDELAY_H do { _delay_us(48); _delay_us(48); _delay_us(48); \ + _delay_us(48); _delay_us(48); _delay_us(48); _delay_us(48); \ + _delay_us(48);_delay_us(48); _delay_us(48); } while (0) /* 480 usec */ +#define OWDELAY_I do { _delay_us(48); _delay_us(22); } while (0) /* 70 usec */ diff -r 4e417d84365e -r b0cb873c0206 1wire-delay.h --- a/1wire-delay.h Mon Apr 10 17:27:48 2006 +0930 +++ /dev/null Thu Jan 01 00:00:00 1970 +0000 @@ -1,43 +0,0 @@ -/* - * Delay routines for the 1 wire bus - * Search routine is copied from the Dallas owpd library with mods. - * - * $Id$ - * - * Copyright (c) 2004 - * Daniel O'Connor . All rights reserved. - * - * Redistribution and use in source and binary forms, with or without - * modification, are permitted provided that the following conditions - * are met: - * 1. Redistributions of source code must retain the above copyright - * notice, this list of conditions and the following disclaimer. - * 2. Redistributions in binary form must reproduce the above copyright - * notice, this list of conditions and the following disclaimer in the - * documentation and/or other materials provided with the distribution. - * - * THIS SOFTWARE IS PROVIDED BY AUTHOR AND CONTRIBUTORS ``AS IS'' AND - * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE - * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE - * ARE DISCLAIMED. IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE - * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL - * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS - * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) - * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT - * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY - * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF - * SUCH DAMAGE. - */ - -#define DELAY_A _delay_us(6) /* 6 usec */ -#define DELAY_B _delay_us(30); _delay_us(30); _delay_us(4) /* 64 usec */ -#define DELAY_C _delay_us(30); _delay_us(30) /* 60 usec */ -#define DELAY_D _delay_us(10) /* 10 usec */ -#define DELAY_E _delay_us(9) /* 9 usec */ -#define DELAY_F _delay_us(25); _delay_us(30); /* 55 usec */ -#define DELAY_G /* 0 usec */ -#define DELAY_H _delay_us(30); _delay_us(30); _delay_us(30); _delay_us(30); \ - _delay_us(30); _delay_us(30); _delay_us(30); _delay_us(30); \ - _delay_us(30); _delay_us(30); _delay_us(30); _delay_us(30); \ - _delay_us(30); _delay_us(30); _delay_us(30); _delay_us(30) /* 480 usec */ -#define DELAY_I _delay_us(30); _delay_us(30);_delay_us(10) /* 70 usec */ diff -r 4e417d84365e -r b0cb873c0206 1wire.c --- a/1wire.c Mon Apr 10 17:27:48 2006 +0930 +++ b/1wire.c Sun Apr 23 22:57:16 2006 +0930 @@ -30,12 +30,18 @@ * SUCH DAMAGE. */ +/* + * No user servicable parts inside + * + * Modify 1wire-config.h + */ + #include #include #include #include #include "1wire.h" -#include "1wire-delay.h" +#include "1wire-config.h" #if OW_DEBUG void uart_putsP(const char *addr); @@ -48,9 +54,13 @@ static uint8_t OW_LastDiscrepancy = 0; static uint8_t OW_LastFamilyDiscrepancy = 0; -static void -OWdelay(void) { - DELAY_I; +/*----------------------------------------------------------------------------- + * Configure the IO port as we need + */ +void +OWInit(void) { + OWBUSINIT(); + OWSETBUSHIGH(); } /*----------------------------------------------------------------------------- @@ -61,18 +71,21 @@ */ uint8_t OWTouchReset(void) { - DELAY_G; + OWDELAY_G; - if (!(OWIREINPORT & _BV(OWIREINPIN))) + /* Check the bus isn't being held low (ie it's broken) Do it after + * the delay so we guarantee we don't see a slave from a previous + * comms attempt + */ + if(OWREADBUS() == 0) return 2; - - OWIREOUTPORT &= ~(_BV(OWIREOUTPIN)); - OWIREDDR |= _BV(OWIREOUTPIN); - DELAY_H; - OWIREDDR &= ~(_BV(OWIREOUTPIN)); - DELAY_I; - return(OWIREINPORT & _BV(OWIREINPIN) ? 1 : 0); + OWSETBUSLOW(); + OWDELAY_H; + OWSETBUSHIGH(); + OWDELAY_I; + + return(OWREADBUS()); } /*----------------------------------------------------------------------------- @@ -80,19 +93,18 @@ */ void OWWriteBit(uint8_t bit) { - OWdelay(); + OWDELAY_I; + if (bit) { - OWIREOUTPORT &= ~(_BV(OWIREOUTPIN)); - OWIREDDR |= _BV(OWIREOUTPIN); - DELAY_A; - OWIREDDR &= ~(_BV(OWIREOUTPIN)); - DELAY_B; + OWSETBUSLOW(); + OWDELAY_A; + OWSETBUSHIGH(); + OWDELAY_B; } else { - OWIREOUTPORT &= ~(_BV(OWIREOUTPIN)); - OWIREDDR |= _BV(OWIREOUTPIN); - DELAY_C; - OWIREDDR &= ~(_BV(OWIREOUTPIN)); - DELAY_D; + OWSETBUSLOW(); + OWDELAY_C; + OWSETBUSHIGH(); + OWDELAY_D; } } @@ -101,14 +113,13 @@ */ uint8_t OWReadBit(void) { - OWdelay(); - - OWIREOUTPORT &= ~(_BV(OWIREOUTPIN)); - OWIREDDR |= _BV(OWIREOUTPIN); - DELAY_A; - OWIREDDR &= ~(_BV(OWIREOUTPIN)); - DELAY_E; - return(OWIREINPORT & _BV(OWIREINPIN) ? 1 : 0); + OWDELAY_I; + + OWSETBUSLOW(); + OWDELAY_A; + OWSETBUSHIGH(); + OWDELAY_E; + return(OWREADBUS()); } /*----------------------------------------------------------------------------- @@ -192,7 +203,6 @@ for (i = 0; i < 8; i++) OWWriteByte(ROM[i]); } - OWWriteByte(cmd); } @@ -277,10 +287,10 @@ OWWriteByte(OW_SEARCH_ROM_CMD); /* issue the search command */ /* pause before beginning the search */ - OWdelay(); - OWdelay(); - OWdelay(); - + OWDELAY_I; + OWDELAY_I; + OWDELAY_I; + /* loop to do the search */ do { /* read a bit and its compliment */ diff -r 4e417d84365e -r b0cb873c0206 1wire.h --- a/1wire.h Mon Apr 10 17:27:48 2006 +0930 +++ b/1wire.h Sun Apr 23 22:57:16 2006 +0930 @@ -1,5 +1,5 @@ /* - * 1 wire header code + * 1 wire header which defines functions and constants * * $Id$ * @@ -28,6 +28,7 @@ * SUCH DAMAGE. */ +void OWInit(void); uint8_t OWTouchReset(void); void OWWriteBit(uint8_t bit); uint8_t OWReadBit(void); @@ -40,13 +41,6 @@ void OWCRC(uint8_t x, uint8_t *crc); void OWSendCmd(uint8_t *ROM, uint8_t cmd); -#define OWIREOUTPORT PORTD -#define OWIREOUTPIN 2 - -#define OWIREINPORT PIND -#define OWIREDDR DDRD -#define OWIREINPIN OWIREOUTPIN - /* Return codes for OWFirst()/OWNext() */ #define OW_BADWIRE -3 #define OW_BADCRC -2 @@ -70,6 +64,13 @@ #define OW_RECALL_CMD 0xb8 #define OW_RD_PSU_CMD 0xb4 +/* DS2502 commands */ +#define OW_READ_MEMORY 0xf0 +#define OW_READ_STATUS 0xaa +#define OW_GEN_CRC 0xc3 +#define OW_WRITE_MEMORY 0x0f +#define OW_WRITE_STATUS 0x55 + /* Family codes */ #define OW_FAMILY_ROM 0x09 #define OW_FAMILY_TEMP 0x10