Created
April 23, 2014 17:18
-
-
Save dmiddlecamp/11224749 to your computer and use it in GitHub Desktop.
OneWire Temp - Multiple Sensors
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
// This #include statement was automatically added by the Spark IDE. | |
#include "TempSensor.h" | |
#include "application.h" | |
#define NUM_SENSORS 2 | |
#ifndef OneWire_h | |
#define OneWire_h | |
#include <inttypes.h> | |
// you can exclude onewire_search by defining that to 0 | |
#ifndef ONEWIRE_SEARCH | |
#define ONEWIRE_SEARCH 1 | |
#endif | |
// You can exclude CRC checks altogether by defining this to 0 | |
#ifndef ONEWIRE_CRC | |
#define ONEWIRE_CRC 1 | |
#endif | |
// You can allow 16-bit CRC checks by defining this to 1 | |
// (Note that ONEWIRE_CRC must also be 1.) | |
#ifndef ONEWIRE_CRC16 | |
#define ONEWIRE_CRC16 1 | |
#endif | |
#define FALSE 0 | |
#define TRUE 1 | |
class OneWire | |
{ | |
private: | |
uint16_t _pin; | |
void DIRECT_WRITE_LOW(void); | |
void DIRECT_MODE_OUTPUT(void); | |
void DIRECT_WRITE_HIGH(void); | |
void DIRECT_MODE_INPUT(void); | |
uint8_t DIRECT_READ(void); | |
#if ONEWIRE_SEARCH | |
// global search state | |
unsigned char ROM_NO[8]; | |
uint8_t LastDiscrepancy; | |
uint8_t LastFamilyDiscrepancy; | |
uint8_t LastDeviceFlag; | |
#endif | |
public: | |
OneWire( uint16_t pin); | |
// Perform a 1-Wire reset cycle. Returns 1 if a device responds | |
// with a presence pulse. Returns 0 if there is no device or the | |
// bus is shorted or otherwise held low for more than 250uS | |
uint8_t reset(void); | |
// Issue a 1-Wire rom select command, you do the reset first. | |
void select(const uint8_t rom[8]); | |
// Issue a 1-Wire rom skip command, to address all on bus. | |
void skip(void); | |
// Write a byte. If 'power' is one then the wire is held high at | |
// the end for parasitically powered devices. You are responsible | |
// for eventually depowering it by calling depower() or doing | |
// another read or write. | |
void write(uint8_t v, uint8_t power = 0); | |
void write_bytes(const uint8_t *buf, uint16_t count, bool power = 0); | |
// Read a byte. | |
uint8_t read(void); | |
void read_bytes(uint8_t *buf, uint16_t count); | |
// Write a bit. The bus is always left powered at the end, see | |
// note in write() about that. | |
void write_bit(uint8_t v); | |
// Read a bit. | |
uint8_t read_bit(void); | |
// Stop forcing power onto the bus. You only need to do this if | |
// you used the 'power' flag to write() or used a write_bit() call | |
// and aren't about to do another read or write. You would rather | |
// not leave this powered if you don't have to, just in case | |
// someone shorts your bus. | |
void depower(void); | |
#if ONEWIRE_SEARCH | |
// Clear the search state so that if will start from the beginning again. | |
void reset_search(); | |
// Setup the search to find the device type 'family_code' on the next call | |
// to search(*newAddr) if it is present. | |
void target_search(uint8_t family_code); | |
// Look for the next device. Returns 1 if a new address has been | |
// returned. A zero might mean that the bus is shorted, there are | |
// no devices, or you have already retrieved all of them. It | |
// might be a good idea to check the CRC to make sure you didn't | |
// get garbage. The order is deterministic. You will always get | |
// the same devices in the same order. | |
uint8_t search(uint8_t *newAddr); | |
#endif | |
#if ONEWIRE_CRC | |
// Compute a Dallas Semiconductor 8 bit CRC, these are used in the | |
// ROM and scratchpad registers. | |
static uint8_t crc8(uint8_t *addr, uint8_t len); | |
#if ONEWIRE_CRC16 | |
// Compute the 1-Wire CRC16 and compare it against the received CRC. | |
// Example usage (reading a DS2408): | |
// // Put everything in a buffer so we can compute the CRC easily. | |
// uint8_t buf[13]; | |
// buf[0] = 0xF0; // Read PIO Registers | |
// buf[1] = 0x88; // LSB address | |
// buf[2] = 0x00; // MSB address | |
// WriteBytes(net, buf, 3); // Write 3 cmd bytes | |
// ReadBytes(net, buf+3, 10); // Read 6 data bytes, 2 0xFF, 2 CRC16 | |
// if (!CheckCRC16(buf, 11, &buf[11])) { | |
// // Handle error. | |
// } | |
// | |
// @param input - Array of bytes to checksum. | |
// @param len - How many bytes to use. | |
// @param inverted_crc - The two CRC16 bytes in the received data. | |
// This should just point into the received data, | |
// *not* at a 16-bit integer. | |
// @param crc - The crc starting value (optional) | |
// @return True, iff the CRC matches. | |
static bool check_crc16(const uint8_t* input, uint16_t len, const uint8_t* inverted_crc, uint16_t crc = 0); | |
// Compute a Dallas Semiconductor 16 bit CRC. This is required to check | |
// the integrity of data received from many 1-Wire devices. Note that the | |
// CRC computed here is *not* what you'll get from the 1-Wire network, | |
// for two reasons: | |
// 1) The CRC is transmitted bitwise inverted. | |
// 2) Depending on the endian-ness of your processor, the binary | |
// representation of the two-byte return value may have a different | |
// byte order than the two bytes you get from 1-Wire. | |
// @param input - Array of bytes to checksum. | |
// @param len - How many bytes to use. | |
// @param crc - The crc starting value (optional) | |
// @return The CRC16, as defined by Dallas Semiconductor. | |
static uint16_t crc16(const uint8_t* input, uint16_t len, uint16_t crc = 0); | |
#endif | |
#endif | |
}; | |
#endif | |
OneWire::OneWire(uint16_t pin) | |
{ | |
pinMode(pin, INPUT); | |
_pin = pin; | |
} | |
void OneWire::DIRECT_WRITE_LOW(void) | |
{ | |
PIN_MAP[_pin].gpio_peripheral->BRR = PIN_MAP[_pin].gpio_pin; | |
} | |
void OneWire::DIRECT_MODE_OUTPUT(void) | |
{ | |
GPIO_TypeDef *gpio_port = PIN_MAP[_pin].gpio_peripheral; | |
uint16_t gpio_pin = PIN_MAP[_pin].gpio_pin; | |
GPIO_InitTypeDef GPIO_InitStructure; | |
if (gpio_port == GPIOA ) | |
{ | |
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE); | |
} | |
else if (gpio_port == GPIOB ) | |
{ | |
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB, ENABLE); | |
} | |
GPIO_InitStructure.GPIO_Pin = gpio_pin; | |
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP; | |
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz; | |
PIN_MAP[_pin].pin_mode = OUTPUT; | |
GPIO_Init(gpio_port, &GPIO_InitStructure); | |
} | |
void OneWire::DIRECT_WRITE_HIGH(void) | |
{ | |
PIN_MAP[_pin].gpio_peripheral->BSRR = PIN_MAP[_pin].gpio_pin; | |
} | |
void OneWire::DIRECT_MODE_INPUT(void) | |
{ | |
GPIO_TypeDef *gpio_port = PIN_MAP[_pin].gpio_peripheral; | |
uint16_t gpio_pin = PIN_MAP[_pin].gpio_pin; | |
GPIO_InitTypeDef GPIO_InitStructure; | |
if (gpio_port == GPIOA ) | |
{ | |
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE); | |
} | |
else if (gpio_port == GPIOB ) | |
{ | |
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB, ENABLE); | |
} | |
GPIO_InitStructure.GPIO_Pin = gpio_pin; | |
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING; | |
PIN_MAP[_pin].pin_mode = INPUT; | |
GPIO_Init(gpio_port, &GPIO_InitStructure); | |
} | |
uint8_t OneWire::DIRECT_READ(void) | |
{ | |
return GPIO_ReadInputDataBit(PIN_MAP[_pin].gpio_peripheral, PIN_MAP[_pin].gpio_pin); | |
} | |
// Perform the onewire reset function. We will wait up to 250uS for | |
// the bus to come high, if it doesn't then it is broken or shorted | |
// and we return a 0; | |
// | |
// Returns 1 if a device asserted a presence pulse, 0 otherwise. | |
// | |
uint8_t OneWire::reset(void) | |
{ | |
uint8_t r; | |
uint8_t retries = 125; | |
noInterrupts(); | |
DIRECT_MODE_INPUT(); | |
interrupts(); | |
// wait until the wire is high... just in case | |
do { | |
if (--retries == 0) return 0; | |
delayMicroseconds(2); | |
} while ( !DIRECT_READ()); | |
noInterrupts(); | |
DIRECT_WRITE_LOW(); | |
DIRECT_MODE_OUTPUT(); // drive output low | |
interrupts(); | |
delayMicroseconds(480); | |
noInterrupts(); | |
DIRECT_MODE_INPUT(); // allow it to float | |
delayMicroseconds(70); | |
r = !DIRECT_READ(); | |
interrupts(); | |
delayMicroseconds(410); | |
return r; | |
} | |
void OneWire::write_bit(uint8_t v) | |
{ | |
if (v & 1) { | |
noInterrupts(); | |
DIRECT_WRITE_LOW(); | |
DIRECT_MODE_OUTPUT(); // drive output low | |
delayMicroseconds(10); | |
DIRECT_WRITE_HIGH(); // drive output high | |
interrupts(); | |
delayMicroseconds(55); | |
} else { | |
noInterrupts(); | |
DIRECT_WRITE_LOW(); | |
DIRECT_MODE_OUTPUT(); // drive output low | |
delayMicroseconds(65); | |
DIRECT_WRITE_HIGH(); // drive output high | |
interrupts(); | |
delayMicroseconds(5); | |
} | |
} | |
// | |
// Read a bit. Port and bit is used to cut lookup time and provide | |
// more certain timing. | |
// | |
uint8_t OneWire::read_bit(void) | |
{ | |
uint8_t r; | |
noInterrupts(); | |
DIRECT_MODE_OUTPUT(); | |
DIRECT_WRITE_LOW(); | |
delayMicroseconds(3); | |
DIRECT_MODE_INPUT(); // let pin float, pull up will raise | |
delayMicroseconds(10); | |
r = DIRECT_READ(); | |
interrupts(); | |
delayMicroseconds(53); | |
return r; | |
} | |
// | |
// Write a byte. The writing code uses the active drivers to raise the | |
// pin high, if you need power after the write (e.g. DS18S20 in | |
// parasite power mode) then set 'power' to 1, otherwise the pin will | |
// go tri-state at the end of the write to avoid heating in a short or | |
// other mishap. | |
// | |
void OneWire::write(uint8_t v, uint8_t power /* = 0 */) { | |
uint8_t bitMask; | |
for (bitMask = 0x01; bitMask; bitMask <<= 1) { | |
OneWire::write_bit( (bitMask & v)?1:0); | |
} | |
if ( !power) { | |
noInterrupts(); | |
DIRECT_MODE_INPUT(); | |
DIRECT_WRITE_LOW(); | |
interrupts(); | |
} | |
} | |
void OneWire::write_bytes(const uint8_t *buf, uint16_t count, bool power /* = 0 */) { | |
for (uint16_t i = 0 ; i < count ; i++) | |
write(buf[i]); | |
if (!power) { | |
noInterrupts(); | |
DIRECT_MODE_INPUT(); | |
DIRECT_WRITE_LOW(); | |
interrupts(); | |
} | |
} | |
// | |
// Read a byte | |
// | |
uint8_t OneWire::read() { | |
uint8_t bitMask; | |
uint8_t r = 0; | |
for (bitMask = 0x01; bitMask; bitMask <<= 1) { | |
if ( OneWire::read_bit()) r |= bitMask; | |
} | |
return r; | |
} | |
void OneWire::read_bytes(uint8_t *buf, uint16_t count) { | |
for (uint16_t i = 0 ; i < count ; i++) | |
buf[i] = read(); | |
} | |
// | |
// Do a ROM select | |
// | |
void OneWire::select(const uint8_t rom[8]) | |
{ | |
uint8_t i; | |
write(0x55); // Choose ROM | |
for (i = 0; i < 8; i++) write(rom[i]); | |
} | |
// | |
// Do a ROM skip | |
// | |
void OneWire::skip() | |
{ | |
write(0xCC); // Skip ROM | |
} | |
void OneWire::depower() | |
{ | |
noInterrupts(); | |
DIRECT_MODE_INPUT(); | |
interrupts(); | |
} | |
#if ONEWIRE_SEARCH | |
// | |
// You need to use this function to start a search again from the beginning. | |
// You do not need to do it for the first search, though you could. | |
// | |
void OneWire::reset_search() | |
{ | |
// reset the search state | |
LastDiscrepancy = 0; | |
LastDeviceFlag = FALSE; | |
LastFamilyDiscrepancy = 0; | |
for(int i = 7; ; i--) { | |
ROM_NO[i] = 0; | |
if ( i == 0) break; | |
} | |
} | |
// Setup the search to find the device type 'family_code' on the next call | |
// to search(*newAddr) if it is present. | |
// | |
void OneWire::target_search(uint8_t family_code) | |
{ | |
// set the search state to find SearchFamily type devices | |
ROM_NO[0] = family_code; | |
for (uint8_t i = 1; i < 8; i++) | |
ROM_NO[i] = 0; | |
LastDiscrepancy = 64; | |
LastFamilyDiscrepancy = 0; | |
LastDeviceFlag = FALSE; | |
} | |
// | |
// Perform a search. If this function returns a '1' then it has | |
// enumerated the next device and you may retrieve the ROM from the | |
// OneWire::address variable. If there are no devices, no further | |
// devices, or something horrible happens in the middle of the | |
// enumeration then a 0 is returned. If a new device is found then | |
// its address is copied to newAddr. Use OneWire::reset_search() to | |
// start over. | |
// | |
// --- Replaced by the one from the Dallas Semiconductor web site --- | |
//-------------------------------------------------------------------------- | |
// Perform the 1-Wire Search Algorithm on the 1-Wire bus using the existing | |
// search state. | |
// Return TRUE : device found, ROM number in ROM_NO buffer | |
// FALSE : device not found, end of search | |
// | |
uint8_t OneWire::search(uint8_t *newAddr) | |
{ | |
uint8_t id_bit_number; | |
uint8_t last_zero, rom_byte_number, search_result; | |
uint8_t id_bit, cmp_id_bit; | |
unsigned char rom_byte_mask, search_direction; | |
// initialize for search | |
id_bit_number = 1; | |
last_zero = 0; | |
rom_byte_number = 0; | |
rom_byte_mask = 1; | |
search_result = 0; | |
// if the last call was not the last one | |
if (!LastDeviceFlag) | |
{ | |
// 1-Wire reset | |
if (!reset()) | |
{ | |
// reset the search | |
LastDiscrepancy = 0; | |
LastDeviceFlag = FALSE; | |
LastFamilyDiscrepancy = 0; | |
return FALSE; | |
} | |
// issue the search command | |
write(0xF0); | |
// loop to do the search | |
do | |
{ | |
// read a bit and its complement | |
id_bit = read_bit(); | |
cmp_id_bit = read_bit(); | |
// check for no devices on 1-wire | |
if ((id_bit == 1) && (cmp_id_bit == 1)) | |
break; | |
else | |
{ | |
// all devices coupled have 0 or 1 | |
if (id_bit != cmp_id_bit) | |
search_direction = id_bit; // 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 (id_bit_number < LastDiscrepancy) | |
search_direction = ((ROM_NO[rom_byte_number] & rom_byte_mask) > 0); | |
else | |
// if equal to last pick 1, if not then pick 0 | |
search_direction = (id_bit_number == LastDiscrepancy); | |
// if 0 was picked then record its position in LastZero | |
if (search_direction == 0) | |
{ | |
last_zero = id_bit_number; | |
// check for Last discrepancy in family | |
if (last_zero < 9) | |
LastFamilyDiscrepancy = last_zero; | |
} | |
} | |
// set or clear the bit in the ROM byte rom_byte_number | |
// with mask rom_byte_mask | |
if (search_direction == 1) | |
ROM_NO[rom_byte_number] |= rom_byte_mask; | |
else | |
ROM_NO[rom_byte_number] &= ~rom_byte_mask; | |
// serial number search direction write bit | |
write_bit(search_direction); | |
// increment the byte counter id_bit_number | |
// and shift the mask rom_byte_mask | |
id_bit_number++; | |
rom_byte_mask <<= 1; | |
// if the mask is 0 then go to new SerialNum byte rom_byte_number and reset mask | |
if (rom_byte_mask == 0) | |
{ | |
rom_byte_number++; | |
rom_byte_mask = 1; | |
} | |
} | |
} | |
while(rom_byte_number < 8); // loop until through all ROM bytes 0-7 | |
// if the search was successful then | |
if (!(id_bit_number < 65)) | |
{ | |
// search successful so set LastDiscrepancy,LastDeviceFlag,search_result | |
LastDiscrepancy = last_zero; | |
// check for last device | |
if (LastDiscrepancy == 0) | |
LastDeviceFlag = TRUE; | |
search_result = TRUE; | |
} | |
} | |
// if no device found then reset counters so next 'search' will be like a first | |
if (!search_result || !ROM_NO[0]) | |
{ | |
LastDiscrepancy = 0; | |
LastDeviceFlag = FALSE; | |
LastFamilyDiscrepancy = 0; | |
search_result = FALSE; | |
} | |
for (int i = 0; i < 8; i++) newAddr[i] = ROM_NO[i]; | |
return search_result; | |
} | |
#endif | |
#if ONEWIRE_CRC | |
// The 1-Wire CRC scheme is described in Maxim Application Note 27: | |
// "Understanding and Using Cyclic Redundancy Checks with Maxim iButton Products" | |
// | |
// | |
// Compute a Dallas Semiconductor 8 bit CRC directly. | |
// this is much slower, but much smaller, than the lookup table. | |
// | |
uint8_t OneWire::crc8( uint8_t *addr, uint8_t len) | |
{ | |
uint8_t crc = 0; | |
while (len--) { | |
uint8_t inbyte = *addr++; | |
for (uint8_t i = 8; i; i--) { | |
uint8_t mix = (crc ^ inbyte) & 0x01; | |
crc >>= 1; | |
if (mix) crc ^= 0x8C; | |
inbyte >>= 1; | |
} | |
} | |
return crc; | |
} | |
#endif | |
#if ONEWIRE_CRC16 | |
bool OneWire::check_crc16(const uint8_t* input, uint16_t len, const uint8_t* inverted_crc, uint16_t crc) | |
{ | |
crc = ~crc16(input, len, crc); | |
return (crc & 0xFF) == inverted_crc[0] && (crc >> 8) == inverted_crc[1]; | |
} | |
uint16_t OneWire::crc16(const uint8_t* input, uint16_t len, uint16_t crc) | |
{ | |
static const uint8_t oddparity[16] = | |
{ 0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0 }; | |
for (uint16_t i = 0 ; i < len ; i++) { | |
// Even though we're just copying a byte from the input, | |
// we'll be doing 16-bit computation with it. | |
uint16_t cdata = input[i]; | |
cdata = (cdata ^ crc) & 0xff; | |
crc >>= 8; | |
if (oddparity[cdata & 0x0F] ^ oddparity[cdata >> 4]) | |
crc ^= 0xC001; | |
cdata <<= 6; | |
crc ^= cdata; | |
cdata <<= 1; | |
crc ^= cdata; | |
} | |
return crc; | |
} | |
#endif | |
OneWire one = OneWire(D3); | |
uint8_t resp[9]; | |
char myIpAddress[24]; | |
char tempfStr[16]; | |
//unsigned int lastTime = 0; | |
TempSensor sensors[NUM_SENSORS]; | |
int checkIndex = 0; | |
void findDevices() { | |
Serial.println("waiting 5 seconds..."); | |
delay(5000); | |
uint8_t addr[12]; | |
int found = 0; | |
while(one.search(addr)) { | |
Serial.print("Found device: "); | |
char *tempID = new char[16]; | |
sprintf(tempID, "%x%x%x%x%x%x%x%x%x", | |
addr[0], addr[0], addr[2] , addr[3] , addr[4] , addr[5], addr[6], addr[7] , addr[8] | |
); | |
sensors[found].id = tempID; | |
for(int i=0;i<9;i++) | |
{ | |
sensors[found].rom[i] = addr[i]; | |
} | |
sensors[found].updated = 0; | |
Serial.print(tempID); | |
Serial.println(""); | |
found++; | |
} | |
} | |
void setup() { | |
Serial.begin(9600); | |
findDevices(); | |
Spark.variable("temperatureF", &tempfStr, STRING); | |
Spark.variable("ipAddress", myIpAddress, STRING); | |
IPAddress myIp = Network.localIP(); | |
sprintf(myIpAddress, "%d.%d.%d.%d", myIp[0], myIp[1], myIp[2], myIp[3]); | |
} | |
void loop() { | |
if (checkIndex >= NUM_SENSORS) { | |
checkIndex = 0; | |
} | |
uint8_t *rom = sensors[checkIndex].rom; | |
delay(1000); | |
//select ROM address | |
// Get the temp | |
one.reset(); | |
one.write(0x55); | |
one.write_bytes(rom,8); | |
one.write(0x44); | |
delay(10); | |
//ask for the temperature from | |
one.reset(); | |
one.write(0x55); | |
one.write_bytes(rom, 8); | |
one.write(0xBE); | |
one.read_bytes(resp, 9); | |
byte MSB = resp[1]; | |
byte LSB = resp[0]; | |
float tempRead = ((MSB << 8) | LSB); //using two's compliment | |
float TemperatureSum = tempRead / 16; | |
//Multiply by 9, then divide by 5, then add 32 | |
float fahrenheit = ((TemperatureSum * 9) / 5) + 32; | |
if (fahrenheit > 7000) { | |
fahrenheit = 7404 - fahrenheit; | |
} | |
sensors[checkIndex].value = fahrenheit; | |
Serial.print("Thermometer ID: "); | |
Serial.println(sensors[checkIndex].id); | |
Serial.println("Value: " + String(fahrenheit)); | |
unsigned int now = millis(); | |
if ((now - sensors[checkIndex].updated) > 60000) { | |
sprintf(tempfStr, "%f", sensors[checkIndex].value); | |
Spark.publish(String("Temperature/") + sensors[checkIndex].id, tempfStr ); | |
sensors[checkIndex].updated = now; | |
} | |
checkIndex++; | |
} |
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
#include "application.h" | |
class TempSensor { | |
public: | |
char *id ; | |
uint8_t rom[8]; | |
float value ; | |
int updated ; | |
}; |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment