mirror of
https://github.com/RobTillaart/Arduino.git
synced 2024-09-20 08:55:59 -04:00
479 lines
8.9 KiB
C++
479 lines
8.9 KiB
C++
//
|
|
// FILE: MCP23S08.cpp
|
|
// AUTHOR: Rob Tillaart
|
|
// VERSION: 0.1.2
|
|
// PURPOSE: Arduino library for SPI MCP23S08 8 channel port expander
|
|
// DATE: 2022-01-10
|
|
// URL: https://github.com/RobTillaart/MCP23S08
|
|
|
|
|
|
#include "Arduino.h"
|
|
#include "MCP23S08.h"
|
|
|
|
|
|
// Registers // description datasheet
|
|
#define MCP23S08_DDR_A 0x00 // Data Direction Register A P..
|
|
#define MCP23S08_POL_A 0x01 // Input Polarity A P..
|
|
#define MCP23S08_GPINTEN_A 0x02 // NOT USED interrupt enable P..
|
|
#define MCP23S08_DEFVAL_A 0x03 // NOT USED interrupt def P..
|
|
#define MCP23S08_INTCON_A 0x04 // NOT USED interrupt control P..
|
|
#define MCP23S08_IOCR 0x05 // IO control register P..
|
|
#define MCP23S08_PUR_A 0x06 // Pull Up Resistors A P..
|
|
#define MCP23S08_INTF_A 0x07 // NOT USED interrupt flag P..
|
|
#define MCP23S08_INTCAP_A 0x08 // NOT USED interrupt capture P..
|
|
#define MCP23S08_GPIO_A 0x09 // General Purpose IO A P..
|
|
#define MCP23S08_OLAT_A 0x0A // NOT USED output latch P..
|
|
|
|
|
|
// low level read / write masks
|
|
#define MCP23S08_WRITE_REG 0x40
|
|
#define MCP23S08_READ_REG 0x41
|
|
|
|
/*
|
|
MCP23S08::MCP23S08()
|
|
{
|
|
}
|
|
*/
|
|
|
|
|
|
MCP23S08::MCP23S08(uint8_t select, uint8_t dataIn, uint8_t dataOut, uint8_t clock, uint8_t address)
|
|
{
|
|
_address = address;
|
|
_select = select;
|
|
_dataIn = dataIn;
|
|
_dataOut = dataOut;
|
|
_clock = clock;
|
|
_error = MCP23S08_OK;
|
|
_hwSPI = false;
|
|
}
|
|
|
|
|
|
MCP23S08::MCP23S08(uint8_t select, uint8_t address)
|
|
{
|
|
_address = address;
|
|
_select = select;
|
|
_error = MCP23S08_OK;
|
|
_hwSPI = true;
|
|
}
|
|
|
|
|
|
bool MCP23S08::begin()
|
|
{
|
|
::pinMode(_select, OUTPUT);
|
|
::digitalWrite(_select, HIGH);
|
|
|
|
_spi_settings = SPISettings(_SPIspeed, MSBFIRST, SPI_MODE0);// 8 MHz - datasheet page 8
|
|
|
|
if (_hwSPI)
|
|
{
|
|
// TODO - ESP32 specific support - see MCP_ADC.
|
|
mySPI = &SPI;
|
|
mySPI->end();
|
|
mySPI->begin();
|
|
}
|
|
else
|
|
{
|
|
::pinMode(_dataIn, INPUT);
|
|
::pinMode(_dataOut, OUTPUT);
|
|
::pinMode(_clock, OUTPUT);
|
|
::digitalWrite(_dataOut, LOW);
|
|
::digitalWrite(_clock, LOW);
|
|
}
|
|
|
|
// check connected
|
|
if (! isConnected()) return false;
|
|
|
|
// disable address increment (datasheet)
|
|
if (! writeReg(MCP23S08_IOCR, 0b00100000)) return false; // TODO MAGIC NR
|
|
// Force INPUT_PULLUP
|
|
if (! writeReg(MCP23S08_PUR_A, 0xFF)) return false;
|
|
return true;
|
|
}
|
|
|
|
|
|
bool MCP23S08::isConnected()
|
|
{
|
|
_error = MCP23S08_OK;
|
|
return true;
|
|
}
|
|
|
|
|
|
// single pin interface
|
|
// pin = 0..7
|
|
// mode = INPUT, OUTPUT, INPUT_PULLUP (= same as INPUT)
|
|
bool MCP23S08::pinMode(uint8_t pin, uint8_t mode)
|
|
{
|
|
if (pin > 7)
|
|
{
|
|
_error = MCP23S08_PIN_ERROR;
|
|
return false;
|
|
}
|
|
if ((mode != INPUT) && (mode != INPUT_PULLUP) && (mode != OUTPUT))
|
|
{
|
|
_error = MCP23S08_VALUE_ERROR;
|
|
return false;
|
|
}
|
|
|
|
uint8_t dataDirectionRegister = MCP23S08_DDR_A;
|
|
uint8_t val = readReg(dataDirectionRegister);
|
|
if (_error != MCP23S08_OK)
|
|
{
|
|
return false;
|
|
}
|
|
uint8_t mask = 1 << pin;
|
|
// only work with valid
|
|
if ((mode == INPUT) || (mode == INPUT_PULLUP))
|
|
{
|
|
val |= mask;
|
|
}
|
|
else if (mode == OUTPUT)
|
|
{
|
|
val &= ~mask;
|
|
}
|
|
// other values won't change val ....
|
|
writeReg(dataDirectionRegister, val);
|
|
if (_error != MCP23S08_OK)
|
|
{
|
|
return false;
|
|
}
|
|
return true;
|
|
}
|
|
|
|
|
|
// pin = 0..7
|
|
// value = LOW, HIGH
|
|
bool MCP23S08::digitalWrite(uint8_t pin, uint8_t value)
|
|
{
|
|
if (pin > 7)
|
|
{
|
|
_error = MCP23S08_PIN_ERROR;
|
|
return false;
|
|
}
|
|
uint8_t IOR = MCP23S08_GPIO_A;
|
|
uint8_t val = readReg(IOR);
|
|
uint8_t pre = val;
|
|
if (_error != MCP23S08_OK)
|
|
{
|
|
return false;
|
|
}
|
|
uint8_t mask = 1 << pin;
|
|
if (value)
|
|
{
|
|
val |= mask;
|
|
}
|
|
else
|
|
{
|
|
val &= ~mask;
|
|
}
|
|
if (pre != val)
|
|
{
|
|
writeReg(IOR, val);
|
|
if (_error != MCP23S08_OK)
|
|
{
|
|
return false;
|
|
}
|
|
}
|
|
return true;
|
|
}
|
|
|
|
|
|
uint8_t MCP23S08::digitalRead(uint8_t pin)
|
|
{
|
|
if (pin > 7)
|
|
{
|
|
_error = MCP23S08_PIN_ERROR;
|
|
return MCP23S08_INVALID_READ;
|
|
}
|
|
uint8_t IOR = MCP23S08_GPIO_A;
|
|
uint8_t val = readReg(IOR);
|
|
if (_error != MCP23S08_OK)
|
|
{
|
|
return MCP23S08_INVALID_READ;
|
|
}
|
|
uint8_t mask = 1 << pin;
|
|
if (val & mask) return HIGH;
|
|
return LOW;
|
|
}
|
|
|
|
|
|
// pin = 0..7
|
|
// reversed = true or false
|
|
bool MCP23S08::setPolarity(uint8_t pin, bool reversed)
|
|
{
|
|
if (pin > 7)
|
|
{
|
|
_error = MCP23S08_PIN_ERROR;
|
|
return false;
|
|
}
|
|
uint8_t inputPolarityRegister = MCP23S08_POL_A;
|
|
uint8_t val = readReg(inputPolarityRegister);
|
|
if (_error != MCP23S08_OK)
|
|
{
|
|
return false;
|
|
}
|
|
uint8_t mask = 1 << pin;
|
|
if (reversed)
|
|
{
|
|
val |= mask;
|
|
}
|
|
else
|
|
{
|
|
val &= ~mask;
|
|
}
|
|
writeReg(inputPolarityRegister, val);
|
|
if (_error != MCP23S08_OK)
|
|
{
|
|
return false;
|
|
}
|
|
return true;
|
|
}
|
|
|
|
|
|
bool MCP23S08::getPolarity(uint8_t pin, bool &reversed)
|
|
{
|
|
if (pin > 7)
|
|
{
|
|
_error = MCP23S08_PIN_ERROR;
|
|
return false;
|
|
}
|
|
uint8_t inputPolarityRegister = MCP23S08_POL_A;
|
|
uint8_t val = readReg(inputPolarityRegister);
|
|
if (_error != MCP23S08_OK)
|
|
{
|
|
return false;
|
|
}
|
|
uint8_t mask = 1 << pin;
|
|
reversed = (val & mask) > 0;
|
|
return true;
|
|
}
|
|
|
|
|
|
// pin = 0..7
|
|
// pullup = true or false
|
|
bool MCP23S08::setPullup(uint8_t pin, bool pullup)
|
|
{
|
|
if (pin > 7)
|
|
{
|
|
_error = MCP23S08_PIN_ERROR;
|
|
return false;
|
|
}
|
|
uint8_t inputPullupRegister = MCP23S08_PUR_A;
|
|
uint8_t val = readReg(inputPullupRegister);
|
|
if (_error != MCP23S08_OK)
|
|
{
|
|
return false;
|
|
}
|
|
uint8_t mask = 1 << pin;
|
|
if (pullup)
|
|
{
|
|
val |= mask;
|
|
}
|
|
else
|
|
{
|
|
val &= ~mask;
|
|
}
|
|
writeReg(inputPullupRegister, val);
|
|
if (_error != MCP23S08_OK)
|
|
{
|
|
return false;
|
|
}
|
|
return true;
|
|
}
|
|
|
|
|
|
bool MCP23S08::getPullup(uint8_t pin, bool &pullup)
|
|
{
|
|
if (pin > 7)
|
|
{
|
|
_error = MCP23S08_PIN_ERROR;
|
|
return false;
|
|
}
|
|
uint8_t inputPullupRegister = MCP23S08_PUR_A;
|
|
uint8_t val = readReg(inputPullupRegister);
|
|
if (_error != MCP23S08_OK)
|
|
{
|
|
return false;
|
|
}
|
|
uint8_t mask = 1 << pin;
|
|
pullup = (val & mask) > 0;
|
|
return true;
|
|
}
|
|
|
|
|
|
void MCP23S08::setSPIspeed(uint32_t speed)
|
|
{
|
|
_SPIspeed = speed;
|
|
_spi_settings = SPISettings(_SPIspeed, MSBFIRST, SPI_MODE0);
|
|
};
|
|
|
|
|
|
|
|
///////////////////////////////////////////////////////////////////////
|
|
//
|
|
// 8 pins interface
|
|
// whole register at once
|
|
// value = 0..0xFF bit pattern
|
|
bool MCP23S08::pinMode8(uint8_t value)
|
|
{
|
|
writeReg(MCP23S08_DDR_A, value);
|
|
_error = MCP23S08_OK;
|
|
return true;
|
|
}
|
|
|
|
|
|
bool MCP23S08::write8(uint8_t value)
|
|
{
|
|
writeReg(MCP23S08_GPIO_A, value);
|
|
_error = MCP23S08_OK;
|
|
return true;
|
|
}
|
|
|
|
|
|
int MCP23S08::read8()
|
|
{
|
|
_error = MCP23S08_OK;
|
|
return readReg(MCP23S08_GPIO_A);
|
|
}
|
|
|
|
|
|
// mask = 0..0xFF bit pattern
|
|
bool MCP23S08::setPolarity8(uint8_t mask)
|
|
{
|
|
writeReg(MCP23S08_POL_A, mask);
|
|
if (_error != MCP23S08_OK)
|
|
{
|
|
return false;
|
|
}
|
|
return true;
|
|
}
|
|
|
|
|
|
bool MCP23S08::getPolarity8(uint8_t &mask)
|
|
{
|
|
mask = readReg(MCP23S08_POL_A);
|
|
if (_error != MCP23S08_OK)
|
|
{
|
|
return false;
|
|
}
|
|
return true;
|
|
}
|
|
|
|
|
|
// mask = 0..0xFF bit pattern
|
|
bool MCP23S08::setPullup8(uint8_t mask)
|
|
{
|
|
writeReg(MCP23S08_PUR_A, mask);
|
|
if (_error != MCP23S08_OK)
|
|
{
|
|
return false;
|
|
}
|
|
return true;
|
|
}
|
|
|
|
|
|
bool MCP23S08::getPullup8(uint8_t &mask)
|
|
{
|
|
mask = readReg(MCP23S08_PUR_A);
|
|
if (_error != MCP23S08_OK)
|
|
{
|
|
return false;
|
|
}
|
|
return true;
|
|
}
|
|
|
|
|
|
int MCP23S08::lastError()
|
|
{
|
|
int e = _error;
|
|
_error = MCP23S08_OK; // reset error after read.
|
|
return e;
|
|
}
|
|
|
|
|
|
////////////////////////////////////////////////////
|
|
//
|
|
// PRIVATE
|
|
//
|
|
|
|
bool MCP23S08::writeReg(uint8_t reg, uint8_t value)
|
|
{
|
|
_error = MCP23S08_OK;
|
|
|
|
if (reg > MCP23S08_OLAT_A)
|
|
{
|
|
_error = MCP23S08_REGISTER_ERROR;
|
|
return false;
|
|
}
|
|
::digitalWrite(_select, LOW);
|
|
if (_hwSPI)
|
|
{
|
|
mySPI->beginTransaction(_spi_settings);
|
|
mySPI->transfer(MCP23S08_WRITE_REG | (_address << 1) );
|
|
mySPI->transfer(reg);
|
|
mySPI->transfer(value);
|
|
mySPI->endTransaction();
|
|
}
|
|
else
|
|
{
|
|
swSPI_transfer(MCP23S08_WRITE_REG | (_address << 1) );
|
|
swSPI_transfer(reg);
|
|
swSPI_transfer(value);
|
|
}
|
|
::digitalWrite(_select, HIGH);
|
|
return true;
|
|
}
|
|
|
|
|
|
uint8_t MCP23S08::readReg(uint8_t reg)
|
|
{
|
|
uint8_t rv = 0;
|
|
|
|
_error = MCP23S08_OK;
|
|
|
|
if (reg > MCP23S08_OLAT_A)
|
|
{
|
|
_error = MCP23S08_REGISTER_ERROR;
|
|
return false;
|
|
}
|
|
|
|
::digitalWrite(_select, LOW);
|
|
if (_hwSPI)
|
|
{
|
|
mySPI->beginTransaction(_spi_settings);
|
|
mySPI->transfer(MCP23S08_READ_REG | (_address << 1) ); // TODO OPTIMIZE n times
|
|
mySPI->transfer(reg);
|
|
rv = mySPI->transfer(0xFF);
|
|
mySPI->endTransaction();
|
|
}
|
|
else
|
|
{
|
|
swSPI_transfer(MCP23S08_READ_REG | (_address << 1) );
|
|
swSPI_transfer(reg);
|
|
rv = swSPI_transfer(0xFF);
|
|
}
|
|
::digitalWrite(_select, HIGH);
|
|
return rv;
|
|
}
|
|
|
|
|
|
uint8_t MCP23S08::swSPI_transfer(uint8_t value)
|
|
{
|
|
uint8_t clk = _clock;
|
|
uint8_t dao = _dataOut;
|
|
uint8_t dai = _dataIn;
|
|
|
|
uint8_t rv = 0;
|
|
for (uint8_t mask = 0x80; mask > 0; mask >>= 1)
|
|
{
|
|
::digitalWrite(dao, (value & mask) ? HIGH : LOW);
|
|
::digitalWrite(clk, HIGH);
|
|
if (::digitalRead(dai) == HIGH) rv |= mask;
|
|
::digitalWrite(clk, LOW);
|
|
}
|
|
return rv;
|
|
}
|
|
|
|
|
|
// -- END OF FILE --
|
|
|