#pragma once
//
//    FILE: MCP23S17.h
//  AUTHOR: Rob Tillaart
// VERSION: 0.2.2
// PURPOSE: Arduino library for SPI MCP23S17 16 channel port expander
//    DATE: 2021-12-30
//     URL: https://github.com/RobTillaart/MCP23S17


#include "Arduino.h"
#include "SPI.h"


#define MCP23S17_LIB_VERSION              (F("0.2.2"))

#define MCP23S17_OK                       0x00
#define MCP23S17_PIN_ERROR                0x81
#define MCP23S17_SPI_ERROR                0x82
#define MCP23S17_VALUE_ERROR              0x83
#define MCP23S17_PORT_ERROR               0x84
#define MCP23S17_REGISTER_ERROR           0xFF


#define MCP23S17_INVALID_READ             0xFF


const uint32_t MCP23S17_TYP_SPI_SPEED =  8000000;
const uint32_t MCP23S17_MAX_SPI_SPEED = 10000000;



class MCP23S17
{
public:
  //  SW SPI
  MCP23S17(uint8_t select, uint8_t dataIn, uint8_t dataOut, uint8_t clock, uint8_t address = 0x00);
  //  HW SPI
  MCP23S17(uint8_t select, SPIClass* spi);
  MCP23S17(uint8_t select, uint8_t address = 0x00, SPIClass* spi = &SPI);

  bool     begin();
  bool     isConnected();
  uint8_t  getAddress();   //  typically returns 0x00


  //  single pin interface
  //  mode = INPUT, OUTPUT or INPUT_PULLUP (==INPUT)
  bool     pinMode(uint8_t pin, uint8_t mode);
  bool     digitalWrite(uint8_t pin, uint8_t value);
  uint8_t  digitalRead(uint8_t pin);

  bool     setPolarity(uint8_t pin, bool reversed);
  bool     getPolarity(uint8_t pin, bool &reversed);
  bool     setPullup(uint8_t pin, bool pullup);
  bool     getPullup(uint8_t pin, bool &pullup);


  //  8 pins interface
  //  port  = 0..1
  //  value = bit pattern
  bool     pinMode8(uint8_t port, uint8_t value);
  bool     write8(uint8_t port, uint8_t value);
  int      read8(uint8_t port);

  bool     setPolarity8(uint8_t port, uint8_t mask);
  bool     getPolarity8(uint8_t port, uint8_t &mask);
  bool     setPullup8(uint8_t port, uint8_t mask);
  bool     getPullup8(uint8_t port, uint8_t &mask);


  //  16 pins interface
  //  value = bit pattern
  bool     pinMode16(uint16_t value);
  bool     write16(uint16_t value);
  uint16_t read16();

  bool     setPolarity16(uint16_t mask);
  bool     getPolarity16(uint16_t &mask);
  bool     setPullup16(uint16_t mask);
  bool     getPullup16(uint16_t &mask);


  //       speed in Hz
  void     setSPIspeed(uint32_t speed);
  uint32_t getSPIspeed() { return _SPIspeed; };

  //       debugging
  bool     usesHWSPI() { return _hwSPI; };
  int      lastError();

private:
  bool     writeReg(uint8_t reg, uint8_t value);
  uint8_t  readReg(uint8_t reg);

  uint8_t  _address = 0;
  uint8_t  _select  = 0;
  uint8_t  _dataOut = 0;
  uint8_t  _dataIn  = 0;
  uint8_t  _clock   = 0;
  uint8_t  _error   = MCP23S17_OK;

  bool        _hwSPI = true;
  //  10 MHz is maximum, 8 is a better clock divider
  uint32_t    _SPIspeed = MCP23S17_TYP_SPI_SPEED;
  SPIClass *  _mySPI;
  SPISettings _spi_settings;

  uint8_t  swSPI_transfer(uint8_t val);
};


// -- END OF FILE --