IoAbstraction.h File Reference

Using basic IoFacilities allows one to abstract away the use of IoExpanders, such that the switching from BasicIoFacilities to IoExpanderFacilities allows the same code to use an IoExpander instead of direct pins. More...

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Classes
struct	ShiftRegConfig
class	ShiftRegisterIoAbstraction
class	ShiftRegisterIoAbstraction165In
class	MultiIoAbstraction

Typedefs
typedef uint8_t(*	ExpanderOpFn) (IoAbstractionRef ref, uint8_t pin, uint8_t val)
typedef MultiIoAbstraction *	MultiIoAbstractionRef

Enumerations
enum	ShiftBitOrder { MSBFIRST , LSBFIRST }

Functions
uint8_t	shiftIn (pinid_t dataPin, pinid_t clockPin, ShiftBitOrder bitOrder)
IoAbstractionRef	inputOutputFromShiftRegister (uint8_t readClockPin, uint8_t readDataPin, uint8_t readLatchPin, uint8_t numOfReadDevices, uint8_t writeClockPin, uint8_t writeDataPin, uint8_t writeLatchPin, uint8_t numOfWriteDevices)
IoAbstractionRef	inputOutputFromShiftRegister (uint8_t readClockPin, uint8_t readDataPin, uint8_t readLatchPin, uint8_t writeClockPin, uint8_t writeDataPin, uint8_t writeLatchPin)
IoAbstractionRef	inputOnlyFromShiftRegister (uint8_t readClockPin, uint8_t dataPin, uint8_t latchPin, uint8_t numOfDevicesRead=1)
IoAbstractionRef	outputOnlyFromShiftRegister (uint8_t writeClockPin, uint8_t writeDataPin, uint8_t writeLatchPin, uint8_t numOfDevicesWrite=1)
IoAbstractionRef	inputFrom74HC165ShiftRegister (pinid_t readClkPin, pinid_t dataPin, pinid_t latchPin, pinid_t numOfDevices=1)
MultiIoAbstractionRef	multiIoExpander (pinid_t arduinoPinRange)
void	multiIoAddExpander (MultiIoAbstractionRef multiIo, IoAbstractionRef expander, pinid_t pinRange)

Detailed Description

Using basic IoFacilities allows one to abstract away the use of IoExpanders, such that the switching from BasicIoFacilities to IoExpanderFacilities allows the same code to use an IoExpander instead of direct pins.

Typedef Documentation

MultiIoAbstractionRef

typedef MultiIoAbstraction* MultiIoAbstractionRef

A reference specifically to a MultiIoAbstraction that can be passed to any of the ioDevice calls, but can also have more IO expanders added to it.

Function Documentation

inputOutputFromShiftRegister() [1/2]

IoAbstractionRef inputOutputFromShiftRegister	(	uint8_t	readClockPin,
		uint8_t	readDataPin,
		uint8_t	readLatchPin,
		uint8_t	numOfReadDevices,
		uint8_t	writeClockPin,
		uint8_t	writeDataPin,
		uint8_t	writeLatchPin,
		uint8_t	numOfWriteDevices
	)

performs both input and output functions using two or more shift registers, for both reading and writing. As shift registers have a fixed direction input and output are handled by different devices, and therefore fixed at the time of building the circuit. This function supports chaining of up to 4 devices for both directions.

This abstraction works as follows:

• Input pins of the input shift register start at 0
• Output pins of the output shift register start at 32.

Parameters

readClockPin	the clock pin on the INPUT shift register
readDataPin	the data pin on the INPUT shift register
readLatchPin	the latch pin on the INPUT shift register
numOfDevicesRead	the number of shift registers that have been chained for reading
writeClockPin	the clock pin on the OUTPUT shift register
writeDataPin	the data pin on the OUTPUT shift register
writeLatchPin	the latch pin on the OUTPUT shift register
numOfDevicesWrite	the number of shift registers that have been chained for writing

inputOutputFromShiftRegister() [2/2]

IoAbstractionRef inputOutputFromShiftRegister	(	uint8_t	readClockPin,
		uint8_t	readDataPin,
		uint8_t	readLatchPin,
		uint8_t	writeClockPin,
		uint8_t	writeDataPin,
		uint8_t	writeLatchPin
	)

performs both input and output functions using two shift registers, one for reading and one for writing. As shift registers have a fixed direction input and output are handled by different devices, and therefore fixed at the time of building the circuit. This function is for when you have a single input and single output device. See the other version of the function if you need to chain devices.

This abstraction works as follows:

• Input pins of the input shift register start at 0
• Output pins of the output shift register start at 32.

Parameters

readClockPin	the clock pin on the INPUT shift register
readDataPin	the data pin on the INPUT shift register
readLatchPin	the latch pin on the INPUT shift register
writeClockPin	the clock pin on the OUTPUT shift register
writeDataPin	the data pin on the OUTPUT shift register
writeLatchPin	the latch pin on the OUTPUT shift register

inputOnlyFromShiftRegister()

IoAbstractionRef inputOnlyFromShiftRegister	(	uint8_t	readClockPin,
		uint8_t	dataPin,
		uint8_t	latchPin,
		uint8_t	numOfDevicesRead = 1
	)

performs input only functions using a shift register, the input pins of the shift register start at pin 0.

Parameters

readClockPin	the clock pin on the INPUT shift register
dataPin	the data pin on the INPUT shift register
latchPin	the latch pin on the INPUT shift register

outputOnlyFromShiftRegister()

IoAbstractionRef outputOnlyFromShiftRegister	(	uint8_t	writeClockPin,
		uint8_t	writeDataPin,
		uint8_t	writeLatchPin,
		uint8_t	numOfDevicesWrite = 1
	)

performs output only functions using a shift register, the output pins of the shift register start at 32.

Parameters

writeClockPin	the clock pin on the OUTPUT shift register
writeDataPin	the data pin on the OUTPUT shift register
writeLatchPin	the latch pin on the OUTPUT shift register

inputFrom74HC165ShiftRegister()

IoAbstractionRef inputFrom74HC165ShiftRegister	(	pinid_t	readClkPin,
		pinid_t	dataPin,
		pinid_t	latchPin,
		pinid_t	numOfDevices = 1
	)

Performs input only functions using a 74x165 plugin, the input pins start at 0 up to a maximum of 31, each device adds another 8 pins.

Parameters

readClkPin	the clock pin of the shift register, used as OUTPUT
dataPin	the data pin of the shift register, used as INPUT
latchPin	the latch pin of the shift register, used as OUTPUT
numOfDevices	the number of devices that are chained together in the usual fashion, range is 1..4

Returns

a shift register abstraction as an IoAbstraction ref.

multiIoExpander()

MultiIoAbstractionRef multiIoExpander ( pinid_t  arduinoPinRange )

inline

Create a multiIoExpander by adding together more than one IoAbstraction, for example Arduino pins plus a few 8574 devices.

Parameters

arduinoPinRange

the number of pins to assign to Arduino.

multiIoAddExpander()

void multiIoAddExpander ( MultiIoAbstractionRef  multiIo, IoAbstractionRef  expander, pinid_t  pinRange  )

inline

Add an additional expander to an existing multiIoExpander.

Parameters

expander	the expander to be added
pinRange	the number of pins needed by the expander.