| User | Revision | Line number | New contents of line |
|---|
| gbeardall |
0:2f78e3dca55d
|
1
|
/*
|
| gbeardall |
0:2f78e3dca55d
|
2
|
* OneWireThermometer. Base class for Maxim One-Wire Thermometers.
|
| gbeardall |
0:2f78e3dca55d
|
3
|
* Uses the OneWireCRC library.
|
| gbeardall |
0:2f78e3dca55d
|
4
|
*
|
| gbeardall |
0:2f78e3dca55d
|
5
|
* Copyright (C) <2010> Petras Saduikis <petras@petras.co.uk>
|
| gbeardall |
0:2f78e3dca55d
|
6
|
*
|
| gbeardall |
0:2f78e3dca55d
|
7
|
* This file is part of OneWireThermometer.
|
| gbeardall |
0:2f78e3dca55d
|
8
|
*
|
| gbeardall |
0:2f78e3dca55d
|
9
|
* OneWireThermometer is free software: you can redistribute it and/or modify
|
| gbeardall |
0:2f78e3dca55d
|
10
|
* it under the terms of the GNU General Public License as published by
|
| gbeardall |
0:2f78e3dca55d
|
11
|
* the Free Software Foundation, either version 3 of the License, or
|
| gbeardall |
0:2f78e3dca55d
|
12
|
* (at your option) any later version.
|
| gbeardall |
0:2f78e3dca55d
|
13
|
*
|
| gbeardall |
0:2f78e3dca55d
|
14
|
* OneWireThermometer is distributed in the hope that it will be useful,
|
| gbeardall |
0:2f78e3dca55d
|
15
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
| gbeardall |
0:2f78e3dca55d
|
16
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
| gbeardall |
0:2f78e3dca55d
|
17
|
* GNU General Public License for more details.
|
| gbeardall |
0:2f78e3dca55d
|
18
|
*
|
| gbeardall |
0:2f78e3dca55d
|
19
|
* You should have received a copy of the GNU General Public License
|
| gbeardall |
0:2f78e3dca55d
|
20
|
* along with OneWireThermometer. If not, see <http://www.gnu.org/licenses/>.
|
| gbeardall |
0:2f78e3dca55d
|
21
|
*/
|
| gbeardall |
0:2f78e3dca55d
|
22
|
|
| gbeardall |
0:2f78e3dca55d
|
23
|
#include "OneWireThermometer.h"
|
| gbeardall |
0:2f78e3dca55d
|
24
|
#include "OneWireDefs.h"
|
| gbeardall |
0:2f78e3dca55d
|
25
|
#include "DebugTrace.h"
|
| gbeardall |
0:2f78e3dca55d
|
26
|
|
| gbeardall |
0:2f78e3dca55d
|
27
|
DebugTrace pc(ON, TO_SERIAL);
|
| gbeardall |
0:2f78e3dca55d
|
28
|
|
| gbeardall |
0:2f78e3dca55d
|
29
|
// constructor specifies standard speed for the 1-Wire comms
|
| gbeardall |
0:2f78e3dca55d
|
30
|
OneWireThermometer::OneWireThermometer(bool crcOn, bool useAddr, bool parasitic, PinName pin, int device_id) :
|
| gbeardall |
0:2f78e3dca55d
|
31
|
useCRC(crcOn), useAddress(useAddr), useParasiticPower(parasitic),
|
| gbeardall |
0:2f78e3dca55d
|
32
|
oneWire(pin, STANDARD), deviceId(device_id), resolution(twelveBit)
|
| gbeardall |
0:2f78e3dca55d
|
33
|
{
|
| gbeardall |
0:2f78e3dca55d
|
34
|
// NOTE: the power-up resolution of a DS18B20 is 12 bits. The DS18S20's resolution is always
|
| gbeardall |
0:2f78e3dca55d
|
35
|
// 9 bits + enhancement, but we treat the DS18S20 as fixed to 12 bits for calculating the
|
| gbeardall |
0:2f78e3dca55d
|
36
|
// conversion time Tconv.
|
| gbeardall |
0:2f78e3dca55d
|
37
|
}
|
| gbeardall |
0:2f78e3dca55d
|
38
|
|
| gbeardall |
0:2f78e3dca55d
|
39
|
bool OneWireThermometer::initialize()
|
| gbeardall |
0:2f78e3dca55d
|
40
|
{
|
| gbeardall |
0:2f78e3dca55d
|
41
|
// get the device address for use in selectROM() when reading the temperature
|
| gbeardall |
0:2f78e3dca55d
|
42
|
// - not really needed except for device validation if using skipROM()
|
| gbeardall |
0:2f78e3dca55d
|
43
|
if (useAddress)
|
| gbeardall |
0:2f78e3dca55d
|
44
|
{
|
| gbeardall |
0:2f78e3dca55d
|
45
|
pc.traceOut("\r\n");
|
| gbeardall |
0:2f78e3dca55d
|
46
|
pc.traceOut("New Scan\r\n");
|
| gbeardall |
0:2f78e3dca55d
|
47
|
|
| gbeardall |
0:2f78e3dca55d
|
48
|
oneWire.resetSearch();
|
| gbeardall |
0:2f78e3dca55d
|
49
|
if (!oneWire.search(address)) // search for 1-wire device address
|
| gbeardall |
0:2f78e3dca55d
|
50
|
{
|
| gbeardall |
0:2f78e3dca55d
|
51
|
pc.traceOut("No more addresses.\r\n");
|
| gbeardall |
0:2f78e3dca55d
|
52
|
wait(2);
|
| gbeardall |
0:2f78e3dca55d
|
53
|
return false;
|
| gbeardall |
0:2f78e3dca55d
|
54
|
}
|
| gbeardall |
0:2f78e3dca55d
|
55
|
|
| gbeardall |
0:2f78e3dca55d
|
56
|
pc.traceOut("Address = ");
|
| gbeardall |
0:2f78e3dca55d
|
57
|
for (int i = 0; i < ADDRESS_SIZE; i++)
|
| gbeardall |
0:2f78e3dca55d
|
58
|
{
|
| gbeardall |
0:2f78e3dca55d
|
59
|
pc.traceOut("%x ", (int)address[i]);
|
| gbeardall |
0:2f78e3dca55d
|
60
|
}
|
| gbeardall |
0:2f78e3dca55d
|
61
|
pc.traceOut("\r\n");
|
| gbeardall |
0:2f78e3dca55d
|
62
|
|
| gbeardall |
0:2f78e3dca55d
|
63
|
if (OneWireCRC::crc8(address, ADDRESS_CRC_BYTE) != address[ADDRESS_CRC_BYTE]) // check address CRC is valid
|
| gbeardall |
0:2f78e3dca55d
|
64
|
{
|
| gbeardall |
0:2f78e3dca55d
|
65
|
pc.traceOut("CRC is not valid!\r\n");
|
| gbeardall |
0:2f78e3dca55d
|
66
|
wait(2);
|
| gbeardall |
0:2f78e3dca55d
|
67
|
return false;
|
| gbeardall |
0:2f78e3dca55d
|
68
|
}
|
| gbeardall |
0:2f78e3dca55d
|
69
|
|
| gbeardall |
0:2f78e3dca55d
|
70
|
if (address[0] != deviceId)
|
| gbeardall |
0:2f78e3dca55d
|
71
|
{
|
| gbeardall |
0:2f78e3dca55d
|
72
|
// Make sure it is a one-wire thermometer device
|
| gbeardall |
0:2f78e3dca55d
|
73
|
if (DS18B20_ID == deviceId)
|
| gbeardall |
0:2f78e3dca55d
|
74
|
pc.traceOut("You need to use a DS1820 or DS18S20 for correct results.\r\n");
|
| gbeardall |
0:2f78e3dca55d
|
75
|
else if (DS18S20_ID == deviceId)
|
| gbeardall |
0:2f78e3dca55d
|
76
|
pc.traceOut("You need to use a DS18B20 for correct results.\r\n");
|
| gbeardall |
0:2f78e3dca55d
|
77
|
else
|
| gbeardall |
0:2f78e3dca55d
|
78
|
pc.traceOut("Device is not a DS18B20/DS1820/DS18S20 device.\r\n");
|
| gbeardall |
0:2f78e3dca55d
|
79
|
|
| gbeardall |
0:2f78e3dca55d
|
80
|
wait(2);
|
| gbeardall |
0:2f78e3dca55d
|
81
|
return false;
|
| gbeardall |
0:2f78e3dca55d
|
82
|
}
|
| gbeardall |
0:2f78e3dca55d
|
83
|
else
|
| gbeardall |
0:2f78e3dca55d
|
84
|
{
|
| gbeardall |
0:2f78e3dca55d
|
85
|
if (DS18B20_ID == deviceId) pc.traceOut("DS18B20 present and correct.\r\n");
|
| gbeardall |
0:2f78e3dca55d
|
86
|
if (DS18S20_ID == deviceId) pc.traceOut("DS1820/DS18S20 present and correct.\r\n");
|
| gbeardall |
0:2f78e3dca55d
|
87
|
}
|
| gbeardall |
0:2f78e3dca55d
|
88
|
}
|
| gbeardall |
0:2f78e3dca55d
|
89
|
|
| gbeardall |
0:2f78e3dca55d
|
90
|
return true;
|
| gbeardall |
0:2f78e3dca55d
|
91
|
}
|
| gbeardall |
0:2f78e3dca55d
|
92
|
|
| gbeardall |
0:2f78e3dca55d
|
93
|
// NOTE ON USING SKIP ROM: ok to use before a Convert command to get all
|
| gbeardall |
0:2f78e3dca55d
|
94
|
// devices on the bus to do simultaneous temperature conversions. BUT can
|
| gbeardall |
0:2f78e3dca55d
|
95
|
// only use before a Read Scratchpad command if there is only one device on the
|
| gbeardall |
0:2f78e3dca55d
|
96
|
// bus. For purpose of this library it is assumed there is only one device
|
| gbeardall |
0:2f78e3dca55d
|
97
|
// on the bus.
|
| gbeardall |
0:2f78e3dca55d
|
98
|
void OneWireThermometer::resetAndAddress()
|
| gbeardall |
0:2f78e3dca55d
|
99
|
{
|
| gbeardall |
0:2f78e3dca55d
|
100
|
oneWire.reset(); // reset device
|
| gbeardall |
0:2f78e3dca55d
|
101
|
if (useAddress)
|
| gbeardall |
0:2f78e3dca55d
|
102
|
{
|
| gbeardall |
0:2f78e3dca55d
|
103
|
oneWire.matchROM(address); // select which device to talk to
|
| gbeardall |
0:2f78e3dca55d
|
104
|
}
|
| gbeardall |
0:2f78e3dca55d
|
105
|
else
|
| gbeardall |
0:2f78e3dca55d
|
106
|
{
|
| gbeardall |
0:2f78e3dca55d
|
107
|
oneWire.skipROM(); // broadcast
|
| gbeardall |
0:2f78e3dca55d
|
108
|
}
|
| gbeardall |
0:2f78e3dca55d
|
109
|
}
|
| gbeardall |
0:2f78e3dca55d
|
110
|
|
| gbeardall |
0:2f78e3dca55d
|
111
|
bool OneWireThermometer::readAndValidateData(BYTE* data)
|
| gbeardall |
0:2f78e3dca55d
|
112
|
{
|
| gbeardall |
0:2f78e3dca55d
|
113
|
bool dataOk = true;
|
| gbeardall |
0:2f78e3dca55d
|
114
|
|
| gbeardall |
0:2f78e3dca55d
|
115
|
resetAndAddress();
|
| gbeardall |
0:2f78e3dca55d
|
116
|
oneWire.writeByte(READSCRATCH); // read Scratchpad
|
| gbeardall |
0:2f78e3dca55d
|
117
|
|
| gbeardall |
0:2f78e3dca55d
|
118
|
pc.traceOut("read = ");
|
| gbeardall |
0:2f78e3dca55d
|
119
|
for (int i = 0; i < THERMOM_SCRATCHPAD_SIZE; i++)
|
| gbeardall |
0:2f78e3dca55d
|
120
|
{
|
| gbeardall |
0:2f78e3dca55d
|
121
|
// we need all bytes which includes CRC check byte
|
| gbeardall |
0:2f78e3dca55d
|
122
|
data[i] = oneWire.readByte();
|
| gbeardall |
0:2f78e3dca55d
|
123
|
pc.traceOut("%x ", (int)data[i]);
|
| gbeardall |
0:2f78e3dca55d
|
124
|
}
|
| gbeardall |
0:2f78e3dca55d
|
125
|
pc.traceOut("\r\n");
|
| gbeardall |
0:2f78e3dca55d
|
126
|
|
| gbeardall |
0:2f78e3dca55d
|
127
|
// Check CRC is valid if you want to
|
| gbeardall |
0:2f78e3dca55d
|
128
|
if (useCRC && !(OneWireCRC::crc8(data, THERMOM_CRC_BYTE) == data[THERMOM_CRC_BYTE]))
|
| gbeardall |
0:2f78e3dca55d
|
129
|
{
|
| gbeardall |
0:2f78e3dca55d
|
130
|
// CRC failed
|
| gbeardall |
0:2f78e3dca55d
|
131
|
pc.traceOut("CRC FAILED... \r\n");
|
| gbeardall |
0:2f78e3dca55d
|
132
|
dataOk = false;
|
| gbeardall |
0:2f78e3dca55d
|
133
|
}
|
| gbeardall |
0:2f78e3dca55d
|
134
|
|
| gbeardall |
0:2f78e3dca55d
|
135
|
return dataOk;
|
| gbeardall |
0:2f78e3dca55d
|
136
|
}
|
| gbeardall |
0:2f78e3dca55d
|
137
|
|
| gbeardall |
0:2f78e3dca55d
|
138
|
float OneWireThermometer::readTemperature()
|
| gbeardall |
0:2f78e3dca55d
|
139
|
{
|
| gbeardall |
0:2f78e3dca55d
|
140
|
BYTE data[THERMOM_SCRATCHPAD_SIZE];
|
| gbeardall |
0:2f78e3dca55d
|
141
|
float realTemp = -999;
|
| gbeardall |
0:2f78e3dca55d
|
142
|
|
| gbeardall |
0:2f78e3dca55d
|
143
|
resetAndAddress();
|
| gbeardall |
0:2f78e3dca55d
|
144
|
oneWire.writeByte(CONVERT); // issue Convert command
|
| gbeardall |
0:2f78e3dca55d
|
145
|
|
| gbeardall |
0:2f78e3dca55d
|
146
|
if (useParasiticPower)
|
| gbeardall |
0:2f78e3dca55d
|
147
|
{
|
| gbeardall |
0:2f78e3dca55d
|
148
|
// wait while converting - Tconv (according to resolution of reading)
|
| gbeardall |
0:2f78e3dca55d
|
149
|
wait_ms(CONVERSION_TIME[resolution]);
|
| gbeardall |
0:2f78e3dca55d
|
150
|
}
|
| gbeardall |
0:2f78e3dca55d
|
151
|
else
|
| gbeardall |
0:2f78e3dca55d
|
152
|
{
|
| gbeardall |
0:2f78e3dca55d
|
153
|
// TODO
|
| gbeardall |
0:2f78e3dca55d
|
154
|
// after the Convert command, the device should respond by transmitting 0
|
| gbeardall |
0:2f78e3dca55d
|
155
|
// while the temperature conversion is in progress and 1 when the conversion is done
|
| gbeardall |
0:2f78e3dca55d
|
156
|
// - as were are not checking this (TODO), we use Tconv, as we would do for
|
| gbeardall |
0:2f78e3dca55d
|
157
|
// parasitic power
|
| gbeardall |
0:2f78e3dca55d
|
158
|
wait_ms(CONVERSION_TIME[resolution]);
|
| gbeardall |
0:2f78e3dca55d
|
159
|
}
|
| gbeardall |
0:2f78e3dca55d
|
160
|
|
| gbeardall |
0:2f78e3dca55d
|
161
|
if (readAndValidateData(data)) // issue Read Scratchpad commmand and get data
|
| gbeardall |
0:2f78e3dca55d
|
162
|
{
|
| gbeardall |
0:2f78e3dca55d
|
163
|
realTemp = calculateTemperature(data);
|
| gbeardall |
0:2f78e3dca55d
|
164
|
}
|
| gbeardall |
0:2f78e3dca55d
|
165
|
|
| gbeardall |
0:2f78e3dca55d
|
166
|
return realTemp;
|
| gbeardall |
0:2f78e3dca55d
|
167
|
} |
gavin beardall