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# ShiftOutSlow
Arduino library for shiftOut with build-in delay - e.g. for 74HC595
A library for shiftInSlow also exist.
## Description
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ShiftOutSlow is an experimental library that has a build in delay (in microseconds) that allows tuning the time per bit.
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This allows one to improve reliability e.g. when using longer lines.
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The data pin and clock pin are set in the constructor, the delay can be set per byte send to be able to optimize runtime.
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ShiftOutSlow implements the print interface.
## Performance
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The performance of **write()** with a delay of 0 microseconds is slower than the default Arduino
**shiftOut()** due to some overhead.
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The delay requested is divided by two to minimize disruption of the duty cycle of the clock pulse,
resulting in "better" pulses.
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## Interface
The interface exists of the following functions:
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- **ShiftOutSlow(dataPin, clockPin, bitOrder = LSBFIRST)** constructor.
- **size_t write(uint8_t data)** writes a new value. Returns the bytes written.
- **size_t write(const uint8_t \*buffer, size_t size)** writes an array of size over shift out. Uses **write(uint8_t)** so expect about equal performance. Returns the bytes written.
- **uint8_t lastWritten()** returns last value written.
- **void setDelay(uint16_t microSeconds)** set delay per bit from 0 .. 65535 microseconds.
Note that the delay is not the time per bit but an additional time per bit.
Note: the delay can be set runtime per write / print call.
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- **uint16_t getDelay()** returns the set delay in microseconds.
- **bool setBitOrder(bitOrder)** set LSBFIRST or MSBFIRST. Returns false for other values.
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Note: bitorder can be changed runtime per write / print call.
- **uint8_t getBitOrder(void)** returns LSBFIRST or MSBFIRST (typical 0 and 1).
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### Print interface
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As this library implements the print interface one can use:
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- **size_t print(any)** print any data type.
- **size_t println(any)** print any data type followed by a newline "\n".
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## Operation
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See examples.
## Future
- Add a select pin to be more SPI alike?
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