239 lines
6.3 KiB
C
239 lines
6.3 KiB
C
/*
|
|
* Copyright (c) 2005, Swedish Institute of Computer Science
|
|
* 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.
|
|
* 3. Neither the name of the Institute nor the names of its contributors
|
|
* may be used to endorse or promote products derived from this software
|
|
* without specific prior written permission.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE INSTITUTE 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 THE INSTITUTE 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.
|
|
*
|
|
* This file is part of the Contiki operating system.
|
|
*
|
|
* @(#)$Id: ds2411.c,v 1.5 2010/08/25 18:35:52 nifi Exp $
|
|
*/
|
|
/*
|
|
* Device driver for the Dallas Semiconductor DS2411 chip. Heavily
|
|
* based on the application note 126 "1-Wire Communications Through
|
|
* Software".
|
|
*
|
|
* http://www.maxim-ic.com/appnotes.cfm/appnote_number/126
|
|
*/
|
|
|
|
/*
|
|
* For now we stuff in Moteiv Corporation's unique OUI.
|
|
* From http://www.ethereal.com/distribution/manuf.txt:
|
|
* 00:12:75 Moteiv # Moteiv Corporation
|
|
*
|
|
* The EUI-64 is a concatenation of the 24-bit OUI value assigned by
|
|
* the IEEE Registration Authority and a 40-bit extension identifier
|
|
* assigned by the organization with that OUI assignment.
|
|
*/
|
|
|
|
#include <string.h>
|
|
|
|
#include <io.h>
|
|
|
|
#include "contiki.h"
|
|
|
|
#include "dev/ds2411.h"
|
|
|
|
unsigned char ds2411_id[8];
|
|
|
|
#ifdef CONTIKI_TARGET_SKY
|
|
/* 1-wire is at p2.4 */
|
|
#define PIN BV(4)
|
|
|
|
#define PIN_INIT() {\
|
|
P2DIR &= ~PIN; /* p2.4 in, resistor pull high */\
|
|
P2OUT &= ~PIN; /* p2.4 == 0 but still input */\
|
|
}
|
|
|
|
/* Set 1-Wire low or high. */
|
|
#define OUTP_0() (P2DIR |= PIN) /* output and p2.4 == 0 from above */
|
|
#define OUTP_1() (P2DIR &= ~PIN) /* p2.4 in, external resistor pull high */
|
|
|
|
/* Read one bit. */
|
|
#define INP() (P2IN & PIN)
|
|
|
|
/*
|
|
* Delay for u microseconds on a MSP430 at 2.4756MHz.
|
|
*
|
|
* The loop in clock_delay consists of one add and one jnz, i.e 3
|
|
* cycles.
|
|
*
|
|
* 3 cycles at 2.4756MHz ==> 1.2us = 6/5us.
|
|
*
|
|
* Call overhead is roughly 7 cycles and the loop 3 cycles, to
|
|
* compensate for call overheads we make 7/3=14/6 fewer laps in the
|
|
* loop.
|
|
*
|
|
* This macro will loose badly if not passed a constant argument, it
|
|
* relies on the compiler doing the arithmetic during compile time!!
|
|
* TODO: Fix above comment to be correct - below code is modified for 4Mhz
|
|
*/
|
|
#define udelay(u) clock_delay((u*8 - 14)/6)
|
|
|
|
/*
|
|
* Where call overhead dominates, use a macro!
|
|
* Note: modified for 4 Mhz
|
|
*/
|
|
#define udelay_6() { _NOP(); _NOP(); _NOP(); _NOP(); _NOP(); _NOP(); _NOP(); }
|
|
|
|
#endif /* CONTIKI_TARGET_SKY */
|
|
|
|
/*
|
|
* Recommended delay times in us.
|
|
*/
|
|
#define udelay_tA() udelay_6()
|
|
/* tA 6 max 15 */
|
|
#define tB 64
|
|
#define tC 60 /* max 120 */
|
|
#define tD 10
|
|
#define tE 9 /* max 12 */
|
|
#define tF 55
|
|
#define tG 0
|
|
#define tH 480
|
|
#define tI 70
|
|
#define tJ 410
|
|
/*---------------------------------------------------------------------------*/
|
|
static int
|
|
owreset(void)
|
|
{
|
|
int result;
|
|
OUTP_0();
|
|
udelay(tH);
|
|
OUTP_1(); /* Releases the bus */
|
|
udelay(tI);
|
|
result = INP();
|
|
udelay(tJ);
|
|
return result;
|
|
}
|
|
/*---------------------------------------------------------------------------*/
|
|
static void
|
|
owwriteb(unsigned byte)
|
|
{
|
|
int i = 7;
|
|
do {
|
|
if(byte & 0x01) {
|
|
OUTP_0();
|
|
udelay_tA();
|
|
OUTP_1(); /* Releases the bus */
|
|
udelay(tB);
|
|
} else {
|
|
OUTP_0();
|
|
udelay(tC);
|
|
OUTP_1(); /* Releases the bus */
|
|
udelay(tD);
|
|
}
|
|
if(i == 0) {
|
|
return;
|
|
}
|
|
i--;
|
|
byte >>= 1;
|
|
} while(1);
|
|
}
|
|
/*---------------------------------------------------------------------------*/
|
|
static unsigned
|
|
owreadb(void)
|
|
{
|
|
unsigned result = 0;
|
|
int i = 7;
|
|
do {
|
|
OUTP_0();
|
|
udelay_tA();
|
|
OUTP_1(); /* Releases the bus */
|
|
udelay(tE);
|
|
if(INP()) {
|
|
result |= 0x80; /* LSbit first */
|
|
}
|
|
udelay(tF);
|
|
if(i == 0) {
|
|
return result;
|
|
}
|
|
i--;
|
|
result >>= 1;
|
|
} while(1);
|
|
}
|
|
/*---------------------------------------------------------------------------*/
|
|
/* Polynomial ^8 + ^5 + ^4 + 1 */
|
|
static unsigned
|
|
crc8_add(unsigned acc, unsigned byte)
|
|
{
|
|
int i;
|
|
acc ^= byte;
|
|
for(i = 0; i < 8; i++) {
|
|
if(acc & 1) {
|
|
acc = (acc >> 1) ^ 0x8c;
|
|
} else {
|
|
acc >>= 1;
|
|
}
|
|
}
|
|
return acc;
|
|
}
|
|
/*---------------------------------------------------------------------------*/
|
|
int
|
|
ds2411_init()
|
|
{
|
|
int i;
|
|
unsigned family, crc, acc;
|
|
|
|
PIN_INIT();
|
|
|
|
if(owreset() == 0) { /* Something pulled down 1-wire. */
|
|
/*
|
|
* Read MAC id with interrupts disabled.
|
|
*/
|
|
int s = splhigh();
|
|
owwriteb(0x33); /* Read ROM command. */
|
|
family = owreadb();
|
|
/* We receive 6 bytes in the reverse order, LSbyte first. */
|
|
for(i = 7; i >= 2; i--) {
|
|
ds2411_id[i] = owreadb();
|
|
}
|
|
crc = owreadb();
|
|
splx(s);
|
|
|
|
/* Verify family and that CRC match. */
|
|
if(family != 0x01) {
|
|
goto fail;
|
|
}
|
|
acc = crc8_add(0x0, family);
|
|
for(i = 7; i >= 2; i--) {
|
|
acc = crc8_add(acc, ds2411_id[i]);
|
|
}
|
|
if(acc == crc) {
|
|
#ifdef CONTIKI_TARGET_SKY
|
|
/* 00:12:75 Moteiv # Moteiv Corporation */
|
|
ds2411_id[0] = 0x00;
|
|
ds2411_id[1] = 0x12;
|
|
ds2411_id[2] = 0x75;
|
|
#endif /* CONTIKI_TARGET_SKY */
|
|
return 1; /* Success! */
|
|
}
|
|
}
|
|
|
|
fail:
|
|
memset(ds2411_id, 0x0, sizeof(ds2411_id));
|
|
return 0; /* Fail! */
|
|
}
|
|
/*---------------------------------------------------------------------------*/
|