#include <DS18B20.hh>

Inheritance diagram for DS18B20:

Collaboration diagram for DS18B20:

Classes
struct	scratchpad_t

class	Search

Public Types
enum	{ FIRST = -1, ERROR = -1, LAST = ROMBITS }

Public Member Functions
	DS18B20 (OWI pin, const char name=NULL)

	DS18B20 (OWI pin, const uint8_t rom, const char *name=NULL)

bool	connect (uint8_t index)

void	resolution (uint8_t bits)

void	set_trigger (int8_t low, int8_t high)

int16_t	temperature () const

uint8_t	resolution () const

void	get_trigger (int8_t &low, int8_t &high) const

bool	convert_request ()

bool	write_scratchpad ()

bool	read_scratchpad (bool flag=true)

bool	copy_scratchpad ()

bool	recall ()

bool	read_power_supply ()

uint8_t *	rom ()

bool	update_rom ()

int8_t	search_rom (int8_t last=FIRST)

bool	read_rom ()

bool	match_rom ()

bool	skip_rom ()

int8_t	alarm_search (int8_t last=FIRST)

bool	connect (uint8_t family, uint8_t index)

virtual void	on_alarm ()

Static Public Member Functions
static bool	convert_request (OWI *owi, uint8_t resolution=12, bool parasite=false)

static void	print (IOStream &outs, int16_t temp)

Public Attributes
str_P	NAME

Protected Types
enum	{ FAMILY_CODE = 0x28, CONVERT_T = 0x44, READ_SCRATCHPAD = 0xBE, WRITE_SCRATCHPAD = 0x4E, COPY_SCRATCHPAD = 0x48, RECALL_E = 0xB8, READ_POWER_SUPPLY = 0xB4 }

Protected Member Functions
void	power_off ()

int8_t	search (int8_t last=FIRST)

Protected Attributes
scratchpad_t	m_scratchpad

uint8_t	m_parasite

uint32_t	m_start

uint8_t	m_converting

uint8_t	m_rom [ROM_MAX]

const uint8_t *	ROM

Driver *	m_next

OWI *	m_pin

Static Protected Attributes
static const uint8_t	CONFIG_MAX = 3

static const uint16_t	MAX_CONVERSION_TIME = 750

static const uint16_t	MIN_COPY_PULLUP = 10

Friends
IOStream &	operator<< (IOStream &outs, DS18B20 &thermometer)

Detailed Description

Driver for the DS18B20 Programmable Resolution 1-Write Digital Thermometer.

Circuit

                          DS18B20
(VCC)--[4K7]--+       +------------+
(GND)---------)-----1-|GND         |\
(Dn)----------+-----2-|DQ          | |
(VCC/GND)-----------3-|VDD         |/
                      +------------+

May use parasite powering (connect DS18B20 VCC to GND) otherwise to VCC.

References

Maxim Integrated product description (REV: 042208)

Definition at line 49 of file DS18B20.hh.

Member Enumeration Documentation

anonymous enum

protected

DS18B20 Function Commands (Table 3, pp. 12).

Enumerator
FAMILY_CODE
CONVERT_T
READ_SCRATCHPAD
WRITE_SCRATCHPAD
COPY_SCRATCHPAD
RECALL_E
READ_POWER_SUPPLY

Definition at line 248 of file DS18B20.hh.

anonymous enum

inherited

Enumerator
FIRST
ERROR
LAST

Definition at line 60 of file OWI.hh.

Constructor & Destructor Documentation

DS18B20::DS18B20	(	OWI *	pin,
		const char *	name = `NULL`
	)

inline

Construct a DS18B20 device connected to the given 1-Wire bus. Use connect() to lookup, set power supply mode and configuration. Alternatively use read_power_supply() and read_scratchpad() directly if rom address is given.

Parameters

[in]	pin	one wire bus pin.
[in]	name	of device.

Definition at line 80 of file DS18B20.hh.

DS18B20::DS18B20	(	OWI *	pin,
		const uint8_t *	rom,
		const char *	name = `NULL`
	)

inline

Construct a DS18B20 device connected to the given 1-Wire bus and device identity (in EEPROM). Use connect() to lookup, set power supply mode and configuration. Alternatively use read_power_supply() and read_scratchpad() directly if rom address is given.

Parameters

[in]	pin	one wire bus pin.
[in]	rom	device identity.
[in]	name	of device. In program memory (default NULL).

Definition at line 97 of file DS18B20.hh.

Member Function Documentation

int8_t OWI::Driver::alarm_search ( int8_t last = FIRST )

inherited

Search alarming device given the last position of discrepancy. Negative value for start from the beginning.

Parameters

[in] last position of discrepancy.

Returns: position of difference or negative error code.

Definition at line 264 of file OWI.cpp.

bool DS18B20::connect ( uint8_t index )

Connect to DS18B20 device with given index. Reads configuration, scratchpad, and power supply setting. Returns true(1) if connected, otherwise false(0).

Parameters

[in] index device order.

Returns: true(1) if successful otherwise false(0).

Definition at line 34 of file DS18B20.cpp.

bool OWI::Driver::connect	(	uint8_t	family,
		uint8_t	index
	)

inherited

Connect to one-wire device with given family code and index.

Parameters

[in]	family	device family code.
[in]	index	device order.

Returns: true(1) if successful otherwise false(0).

Definition at line 272 of file OWI.cpp.

bool DS18B20::convert_request ( )

Initiate a single temperature conversion. With the default setting 12-bit resolution the max conversion time is 750 ms, MAX_CONVERSION_TIME.

Returns: true(1) if successful otherwise false(0).

Definition at line 50 of file DS18B20.cpp.

bool DS18B20::convert_request	(	OWI *	owi,
		uint8_t	resolution = `12`,
		bool	parasite = `false`
	)

static

Initiate connected devices to perform a simple temperature conversion (boardcast). With the default setting 12-bit resolution the max conversion time is 750 ms, MAX_CONVERSION_TIME. Give zero(0) as resolution to omit conversion wait. Parasite power by passing true for the mode flag. Returns true(1) if successful otherwise false(0).

Parameters

[in]	owi	one-wire interface pin.
[in]	resolution	of conversion.
[in]	parasite	power mode flag.

Returns: true(1) if successful otherwise false(0).

Definition at line 60 of file DS18B20.cpp.

bool DS18B20::copy_scratchpad ( )

Copy device scratchpad triggers and configuration data to device EEPROM. An internal delay is issued to allow the data to be written.

Returns: true(1) if successful otherwise false(0).

Definition at line 101 of file DS18B20.cpp.

void DS18B20::get_trigger	(	int8_t &	low,
		int8_t &	high
	)		const

inline

Get alarm trigger values; low and high threshold values. Use connect(), or read_scratchpad() to read values from device.

Parameters

[out]	low	threshold.
[out]	high	threshold.

Definition at line 165 of file DS18B20.hh.

bool OWI::Driver::match_rom ( )

inherited

Match device rom. Address the slave device with the rom code. Device specific function command should follow. May be used to verify rom code.

Returns: true(1) if successful otherwise false(0).

Definition at line 244 of file OWI.cpp.

virtual void OWI::Driver::on_alarm ( )

inlinevirtualinherited

Callback on alarm dispatch. Default is empty function.

Definition at line 159 of file OWI.hh.

void DS18B20::power_off ( )

inlineprotected

Turn power off if the device is parasite powered. Call connect() or read_power_supply() to set the parasite mode for the device.

Definition at line 293 of file DS18B20.hh.

void DS18B20::print	(	IOStream &	outs,
		int16_t	temp
	)

static

Print temperature reading (fixed point value) to given output stream.

Parameters

[in]	outs	output stream.
[in]	temp	temperature fixed point number.

Definition at line 128 of file DS18B20.cpp.

bool DS18B20::read_power_supply ( )

Read power supply. Determine if the device requires parasite powering. The information is cached and used in read_scratchpad() and copy_scratchpad() for internal delay timing. The function connect() will call this function automatically.

Returns: true(1) if parasite power is required otherwise false(0).

Definition at line 119 of file DS18B20.cpp.

bool OWI::Driver::read_rom ( )

inherited

Read device rom. This can only be used when there is only one slave on the bus.

Returns: true(1) if successful otherwise false(0).

Definition at line 236 of file OWI.cpp.

bool DS18B20::read_scratchpad ( bool flag = true )

Read the contents of the scratchpad to local memory. A internal delay will occur if a convert_request() is pending. The delay is at most max conversion time (750 ms). The flag parameter may be used when a device has been addressed with search (alarm).

Parameters

[in] flag to reset before reading (default true).

Returns: true(1) if successful otherwise false(0).

Definition at line 75 of file DS18B20.cpp.

bool DS18B20::recall ( )

Recall the alarm triggers and configuration from device EEPROM.

Returns: true(1) if successful otherwise false(0).

Definition at line 111 of file DS18B20.cpp.

void DS18B20::resolution ( uint8_t bits )

Set conversion resolution from 9..12 bits. Use write_scratchpad() and copy_scratchpad() to update device.

Parameters

[in] bits resolution.

Definition at line 43 of file DS18B20.cpp.

uint8_t DS18B20::resolution ( ) const

inline

Get conversion resolution. Use connect(), or read_scratchpad() to read values from device before calling this method.

Returns: number of bits.

Definition at line 152 of file DS18B20.hh.

uint8_t* OWI::Driver::rom ( )

inlineinherited

Return pointer to device rom.

Returns: device rom buffer.

Definition at line 96 of file OWI.hh.

int8_t OWI::Driver::search ( int8_t last = FIRST )

protectedinherited

Search device rom given the last position of discrepancy. Negative value for start from the beginning.

Parameters

[in] last position of discrepancy.

Returns: position of difference or negative error code.

Definition at line 182 of file OWI.cpp.

int8_t OWI::Driver::search_rom ( int8_t last = FIRST )

inherited

Search device rom given the last position of discrepancy. Negative value for start from the beginning.

Parameters

[in] last position of discrepancy.

Returns: position of difference or negative error code.

Definition at line 228 of file OWI.cpp.

void DS18B20::set_trigger	(	int8_t	low,
		int8_t	high
	)

inline

Set alarm trigger values; low and high threshold values. Use write_scratchpad() and copy_scratchpad() to update device.

Parameters

[in]	low	threshold.
[in]	high	threshold.

Definition at line 126 of file DS18B20.hh.

bool OWI::Driver::skip_rom ( )

inherited

Skip device rom for boardcast or single device access. Device specific function command should follow.

Returns: true(1) if successful otherwise false(0).

Definition at line 256 of file OWI.cpp.

int16_t DS18B20::temperature ( ) const

inline

Get the latest temperature reading from the local memory scratchpad. Call convert_request() and read_scratchpad() before accessing the scratchpad. Returns at highest resolution a fixed point<12,4> point number. For 11-bit resolution, bit 0 is undefined, 10-bits bit 1 and 0, and so on (LSB).

Returns: temperature

Definition at line 141 of file DS18B20.hh.

bool OWI::Driver::update_rom ( )

inherited

Update the rom identity (in EEPROM). Return true(1) if successful otherwise false(0). Typically used to save configuration after connect(). return bool.

Definition at line 174 of file OWI.cpp.

bool DS18B20::write_scratchpad ( )

Write the contents of the scratchpad triggers and configuration (3 bytes) to device.

Returns: true(1) if successful otherwise false(0).

Definition at line 93 of file DS18B20.cpp.

Friends And Related Function Documentation

IOStream& operator<<	(	IOStream &	outs,
		DS18B20 &	thermometer
	)

friend

Print the name of the thermometer and latest temperature reading with two decimals to given output stream. The temperature is in Celcius.

Parameters

[in]	outs	stream to print device information to.
[in]	thermometer	device.

Returns: iostream.

Definition at line 141 of file DS18B20.cpp.

Member Data Documentation

const uint8_t DS18B20::CONFIG_MAX = 3

staticprotected

Size of configuration; high/low trigger and configuration byte.

Definition at line 272 of file DS18B20.hh.

uint8_t DS18B20::m_converting

protected

Convert request pending.

Definition at line 281 of file DS18B20.hh.

Driver* OWI::Driver::m_next

protectedinherited

Definition at line 164 of file OWI.hh.

uint8_t DS18B20::m_parasite

protected

Parasite power mode.

Definition at line 275 of file DS18B20.hh.

OWI* OWI::Driver::m_pin

protectedinherited

Definition at line 165 of file OWI.hh.

uint8_t OWI::Driver::m_rom[ROM_MAX]

protectedinherited

Definition at line 162 of file OWI.hh.

scratchpad_t DS18B20::m_scratchpad

protected

Definition at line 269 of file DS18B20.hh.

uint32_t DS18B20::m_start

protected

Watchdog millis on convert_request().

Definition at line 278 of file DS18B20.hh.

const uint16_t DS18B20::MAX_CONVERSION_TIME = 750

staticprotected

Max conversion time for 12-bit conversion in milli-seconds.

Definition at line 284 of file DS18B20.hh.

const uint16_t DS18B20::MIN_COPY_PULLUP = 10

staticprotected

Min copy configuration time in milli-seconds (parasite mode).

Definition at line 287 of file DS18B20.hh.

str_P OWI::Driver::NAME

inherited

Name of device driver instance.

Definition at line 67 of file OWI.hh.

const uint8_t* OWI::Driver::ROM

protectedinherited

Definition at line 163 of file OWI.hh.

The documentation for this class was generated from the following files:

libraries/DS18B20/DS18B20.hh
libraries/DS18B20/DS18B20.cpp

Classes

Public Types

Public Member Functions

Static Public Member Functions

Public Attributes

Protected Types

Protected Member Functions

Protected Attributes

Static Protected Attributes

Friends

Detailed Description

Circuit

References

Member Enumeration Documentation

Constructor & Destructor Documentation

Member Function Documentation

Friends And Related Function Documentation

Member Data Documentation