mirror of
https://github.com/RobTillaart/Arduino.git
synced 2024-10-03 18:09:02 -04:00
408 lines
7.7 KiB
C++
408 lines
7.7 KiB
C++
//
|
|
// FILE: MCP23008.cpp
|
|
// AUTHOR: Rob Tillaart
|
|
// VERSION: 0.1.2
|
|
// PURPOSE: Arduino library for I2C MCP23008 8 channel port expander
|
|
// DATE: 2019-10-12
|
|
// URL: https://github.com/RobTillaart/MCP23008
|
|
|
|
|
|
#include "MCP23008.h"
|
|
|
|
|
|
// Registers // DESCRIPTION DATASHEET
|
|
#define MCP23008_DDR_A 0x00 // Data Direction Register A P 10
|
|
#define MCP23008_POL_A 0x01 // Input Polarity A P 11
|
|
#define MCP23008_GPINTEN_A 0x02 // NOT USED interrupt enable P 12
|
|
#define MCP23008_DEFVAL_A 0x03 // NOT USED interrupt def P 13
|
|
#define MCP23008_INTCON_A 0x04 // NOT USED interrupt control P 14
|
|
#define MCP23008_IOCR 0x05 // IO control register P 15
|
|
#define MCP23008_PUR_A 0x06 // Pull Up Resistors A P 16
|
|
#define MCP23008_INTF_A 0x07 // NOT USED interrupt flag P 17
|
|
#define MCP23008_INTCAP_A 0x08 // NOT USED interrupt capture P 18
|
|
#define MCP23008_GPIO_A 0x09 // General Purpose IO A P 19
|
|
#define MCP23008_OLAT_A 0x0A // NOT USED output latch P 20
|
|
|
|
|
|
MCP23008::MCP23008(uint8_t address, TwoWire *wire)
|
|
{
|
|
_address = address;
|
|
_wire = wire;
|
|
_error = MCP23008_OK;
|
|
}
|
|
|
|
|
|
#if defined(ESP8266) || defined(ESP32)
|
|
bool MCP23008::begin(const uint8_t dataPin, const uint8_t clockPin)
|
|
{
|
|
_wire = &Wire;
|
|
_wire->begin(dataPin, clockPin);
|
|
// check connected
|
|
if (! isConnected()) return false;
|
|
// disable address increment (datasheet)
|
|
if (! writeReg(MCP23008_IOCR, 0b00100000)) return false;
|
|
// Force INPUT_PULLUP
|
|
if (! writeReg(MCP23008_PUR_A, 0xFF)) return false;
|
|
return true;
|
|
}
|
|
#endif
|
|
|
|
|
|
bool MCP23008::begin()
|
|
{
|
|
_wire->begin();
|
|
// check connected
|
|
if (! isConnected()) return false;
|
|
// disable address increment (datasheet)
|
|
if (! writeReg(MCP23008_IOCR, 0b00100000)) return false;
|
|
// Force INPUT_PULLUP
|
|
if (! writeReg(MCP23008_PUR_A, 0xFF)) return false;
|
|
return true;
|
|
}
|
|
|
|
|
|
bool MCP23008::isConnected()
|
|
{
|
|
_wire->beginTransmission(_address);
|
|
if (_wire->endTransmission() != 0)
|
|
{
|
|
_error = MCP23008_I2C_ERROR;
|
|
return false;
|
|
}
|
|
_error = MCP23008_OK;
|
|
return true;
|
|
}
|
|
|
|
|
|
// single pin interface
|
|
// pin = 0..7
|
|
// mode = INPUT, OUTPUT, INPUT_PULLUP (= same as INPUT)
|
|
bool MCP23008::pinMode(uint8_t pin, uint8_t mode)
|
|
{
|
|
if (pin > 7)
|
|
{
|
|
_error = MCP23008_PIN_ERROR;
|
|
return false;
|
|
}
|
|
if ((mode != INPUT) && (mode != INPUT_PULLUP) && (mode != OUTPUT))
|
|
{
|
|
_error = MCP23008_VALUE_ERROR;
|
|
return false;
|
|
}
|
|
|
|
uint8_t dataDirectionRegister = MCP23008_DDR_A;
|
|
uint8_t val = readReg(dataDirectionRegister);
|
|
if (_error != MCP23008_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 != MCP23008_OK)
|
|
{
|
|
return false;
|
|
}
|
|
return true;
|
|
}
|
|
|
|
|
|
// pin = 0..7
|
|
// value = LOW, HIGH
|
|
bool MCP23008::digitalWrite(uint8_t pin, uint8_t value)
|
|
{
|
|
if (pin > 7)
|
|
{
|
|
_error = MCP23008_PIN_ERROR;
|
|
return false;
|
|
}
|
|
uint8_t IOR = MCP23008_GPIO_A;
|
|
uint8_t val = readReg(IOR);
|
|
uint8_t pre = val;
|
|
if (_error != MCP23008_OK)
|
|
{
|
|
return false;
|
|
}
|
|
|
|
uint8_t mask = 1 << pin;
|
|
if (value)
|
|
{
|
|
val |= mask;
|
|
}
|
|
else
|
|
{
|
|
val &= ~mask;
|
|
}
|
|
// only write if there is a change
|
|
if (val != pre)
|
|
{
|
|
writeReg(IOR, val);
|
|
if (_error != MCP23008_OK)
|
|
{
|
|
return false;
|
|
}
|
|
}
|
|
return true;
|
|
}
|
|
|
|
|
|
uint8_t MCP23008::digitalRead(uint8_t pin)
|
|
{
|
|
if (pin > 7)
|
|
{
|
|
_error = MCP23008_PIN_ERROR;
|
|
return MCP23008_INVALID_READ;
|
|
}
|
|
uint8_t IOR = MCP23008_GPIO_A;
|
|
uint8_t val = readReg(IOR);
|
|
if (_error != MCP23008_OK)
|
|
{
|
|
return MCP23008_INVALID_READ;
|
|
}
|
|
uint8_t mask = 1 << pin;
|
|
if (val & mask) return HIGH;
|
|
return LOW;
|
|
}
|
|
|
|
|
|
// pin = 0..7
|
|
// reverse = true or false
|
|
bool MCP23008::setPolarity(uint8_t pin, bool reversed)
|
|
{
|
|
if (pin > 7)
|
|
{
|
|
_error = MCP23008_PIN_ERROR;
|
|
return false;
|
|
}
|
|
uint8_t inputPolarityRegister = MCP23008_POL_A;
|
|
uint8_t val = readReg(inputPolarityRegister);
|
|
if (_error != MCP23008_OK)
|
|
{
|
|
return false;
|
|
}
|
|
uint8_t mask = 1 << pin;
|
|
if (reversed)
|
|
{
|
|
val |= mask;
|
|
}
|
|
else
|
|
{
|
|
val &= ~mask;
|
|
}
|
|
writeReg(inputPolarityRegister, val);
|
|
if (_error != MCP23008_OK)
|
|
{
|
|
return false;
|
|
}
|
|
return true;
|
|
}
|
|
|
|
|
|
bool MCP23008::getPolarity(uint8_t pin, bool &reversed)
|
|
{
|
|
if (pin > 7)
|
|
{
|
|
_error = MCP23008_PIN_ERROR;
|
|
return false;
|
|
}
|
|
uint8_t inputPolarityRegister = MCP23008_POL_A;
|
|
uint8_t val = readReg(inputPolarityRegister);
|
|
if (_error != MCP23008_OK)
|
|
{
|
|
return false;
|
|
}
|
|
uint8_t mask = 1 << pin;
|
|
reversed = (val & mask) > 0;
|
|
return true;
|
|
}
|
|
|
|
|
|
// pin = 0..7
|
|
// reverse = true or false
|
|
bool MCP23008::setPullup(uint8_t pin, bool pullup)
|
|
{
|
|
if (pin > 7)
|
|
{
|
|
_error = MCP23008_PIN_ERROR;
|
|
return false;
|
|
}
|
|
uint8_t inputPullupRegister = MCP23008_PUR_A;
|
|
uint8_t val = readReg(inputPullupRegister);
|
|
if (_error != MCP23008_OK)
|
|
{
|
|
return false;
|
|
}
|
|
uint8_t mask = 1 << pin;
|
|
if (pullup)
|
|
{
|
|
val |= mask;
|
|
}
|
|
else
|
|
{
|
|
val &= ~mask;
|
|
}
|
|
writeReg(inputPullupRegister, val);
|
|
if (_error != MCP23008_OK)
|
|
{
|
|
return false;
|
|
}
|
|
return true;
|
|
}
|
|
|
|
|
|
bool MCP23008::getPullup(uint8_t pin, bool &pullup)
|
|
{
|
|
if (pin > 7)
|
|
{
|
|
_error = MCP23008_PIN_ERROR;
|
|
return false;
|
|
}
|
|
uint8_t inputPullupRegister = MCP23008_PUR_A;
|
|
uint8_t val = readReg(inputPullupRegister);
|
|
if (_error != MCP23008_OK)
|
|
{
|
|
return false;
|
|
}
|
|
uint8_t mask = 1 << pin;
|
|
pullup = (val & mask) > 0;
|
|
return true;
|
|
}
|
|
|
|
|
|
///////////////////////////////////////////////////////////////////////
|
|
//
|
|
// 8 pins interface
|
|
// whole register at once
|
|
// value = 0..0xFF bit pattern
|
|
bool MCP23008::pinMode8(uint8_t value)
|
|
{
|
|
writeReg(MCP23008_DDR_A, value);
|
|
_error = MCP23008_OK;
|
|
return true;
|
|
}
|
|
|
|
|
|
bool MCP23008::write8(uint8_t value)
|
|
{
|
|
writeReg(MCP23008_GPIO_A, value);
|
|
_error = MCP23008_OK;
|
|
return true;
|
|
}
|
|
|
|
|
|
int MCP23008::read8()
|
|
{
|
|
_error = MCP23008_OK;
|
|
return readReg(MCP23008_GPIO_A);
|
|
}
|
|
|
|
|
|
// mask = 0..0xFF bit pattern
|
|
bool MCP23008::setPolarity8(uint8_t mask)
|
|
{
|
|
writeReg(MCP23008_POL_A, mask);
|
|
if (_error != MCP23008_OK)
|
|
{
|
|
return false;
|
|
}
|
|
return true;
|
|
}
|
|
|
|
|
|
bool MCP23008::getPolarity8(uint8_t &mask)
|
|
{
|
|
mask = readReg(MCP23008_POL_A);
|
|
if (_error != MCP23008_OK)
|
|
{
|
|
return false;
|
|
}
|
|
return true;
|
|
}
|
|
|
|
|
|
// mask = 0..0xFF bit pattern
|
|
bool MCP23008::setPullup8(uint8_t mask)
|
|
{
|
|
writeReg(MCP23008_PUR_A, mask);
|
|
if (_error != MCP23008_OK)
|
|
{
|
|
return false;
|
|
}
|
|
return true;
|
|
}
|
|
|
|
|
|
bool MCP23008::getPullup8(uint8_t &mask)
|
|
{
|
|
mask = readReg(MCP23008_PUR_A);
|
|
if (_error != MCP23008_OK)
|
|
{
|
|
return false;
|
|
}
|
|
return true;
|
|
}
|
|
|
|
|
|
int MCP23008::lastError()
|
|
{
|
|
int e = _error;
|
|
_error = MCP23008_OK; // reset error after read.
|
|
return e;
|
|
}
|
|
|
|
|
|
////////////////////////////////////////////////////
|
|
//
|
|
// PRIVATE
|
|
//
|
|
|
|
bool MCP23008::writeReg(uint8_t reg, uint8_t value)
|
|
{
|
|
_wire->beginTransmission(_address);
|
|
_wire->write(reg);
|
|
_wire->write(value);
|
|
if (_wire->endTransmission() != 0)
|
|
{
|
|
_error = MCP23008_I2C_ERROR;
|
|
return false;
|
|
}
|
|
_error = MCP23008_OK;
|
|
return true;
|
|
}
|
|
|
|
|
|
uint8_t MCP23008::readReg(uint8_t reg)
|
|
{
|
|
_wire->beginTransmission(_address);
|
|
_wire->write(reg);
|
|
if (_wire->endTransmission() != 0)
|
|
{
|
|
_error = MCP23008_I2C_ERROR;
|
|
return 0;
|
|
}
|
|
else
|
|
{
|
|
_error = MCP23008_OK;
|
|
}
|
|
uint8_t n = _wire->requestFrom(_address, (uint8_t)1);
|
|
if (n != 1)
|
|
{
|
|
_error = MCP23008_I2C_ERROR;
|
|
return 0;
|
|
}
|
|
return _wire->read();
|
|
}
|
|
|
|
|
|
// -- END OF FILE --
|
|
|