FastShiftInOut

Arduino library for AVR optimized shiftInOut (simultaneously).

Related libraries

• https://github.com/RobTillaart/FastShiftIn
• https://github.com/RobTillaart/FastShiftOut
• https://github.com/RobTillaart/ShiftInSlow
• https://github.com/RobTillaart/ShiftOutSlow

Description

FastShiftInOut is a class that can send and receive bytes simultaneously. In that sense it mimics a SPI bus.

Experimental.

Performance

performance of write()

version	UNO (us)	ESP32 (us)
0.1.0	181.08	4.32
0.1.1	26.84	4.32
0.1.2	26.84	no data
0.1.3	25.52	4.32

Interface

#include "FastShiftInOut.h"

Functions

bitOrder = { LSBFIRST, MSBFIRST };

• FastShiftInOut(uint8_t dataIn, uint8_t dataOut, uint8_t clockPin, uint8_t bitOrder = LSBFIRST) Constructor.
• uint8_t write(uint8_t data) reads and writes simultaneously.
• uint8_t lastWritten(void) returns last byte written.
• uint8_t lastRead(void) returns last byte read.
• bool setBitOrder(uint8_t bitOrder) bitOrder must be LSBFIRST or MSBFIRST.
• uint8_t getBitOrder(void) idem.
• uint8_t writeLSBFIRST(uint8_t data) optimized version, in practice almost no difference.
• uint8_t writeMSBFIRST(uint8_t data) optimized version, in practice almost no difference.

Future

Must

• documentation
• follow FastShiftIn and FastShiftOut

Should

Could

• void ignoreRead()
• add Print interface?

Wont

Support

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Thank you,