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/***************************************************
This is a library for the MCP23008 i2c port expander
These displays use I2C to communicate, 2 pins are required to
interface
Adafruit invests time and resources providing this open source code,
please support Adafruit and open-source hardware by purchasing
products from Adafruit!
Written by Limor Fried/Ladyada for Adafruit Industries.
BSD license, all text above must be included in any redistribution
****************************************************/
#if ARDUINO >= 100
#include "Arduino.h"
#else
#include "WProgram.h"
#endif
#include <Wire.h>
#include <avr/pgmspace.h>
#include "Adafruit_MCP23008.h"
////////////////////////////////////////////////////////////////////////////////
// RTC_DS1307 implementation
void Adafruit_MCP23008::begin(uint8_t addr) {
if (addr > 7) {
addr = 7;
}
i2caddr = addr;
Wire.begin();
// set defaults!
Wire.beginTransmission(MCP23008_ADDRESS | i2caddr);
#if ARDUINO >= 100
Wire.write((byte)MCP23008_IODIR);
Wire.write((byte)0xFF); // all inputs
Wire.write((byte)0x00);
Wire.write((byte)0x00);
Wire.write((byte)0x00);
Wire.write((byte)0x00);
Wire.write((byte)0x00);
Wire.write((byte)0x00);
Wire.write((byte)0x00);
Wire.write((byte)0x00);
Wire.write((byte)0x00);
#else
Wire.send(MCP23008_IODIR);
Wire.send(0xFF); // all inputs
Wire.send(0x00);
Wire.send(0x00);
Wire.send(0x00);
Wire.send(0x00);
Wire.send(0x00);
Wire.send(0x00);
Wire.send(0x00);
Wire.send(0x00);
Wire.send(0x00);
#endif
Wire.endTransmission();
}
void Adafruit_MCP23008::begin(void) {
begin(0);
}
void Adafruit_MCP23008::pinMode(uint8_t p, uint8_t d) {
uint8_t iodir;
// only 8 bits!
if (p > 7)
return;
iodir = read8(MCP23008_IODIR);
// set the pin and direction
if (d == INPUT) {
iodir |= 1 << p;
} else {
iodir &= ~(1 << p);
}
// write the new IODIR
write8(MCP23008_IODIR, iodir);
}
uint8_t Adafruit_MCP23008::readGPIO(void) {
// read the current GPIO output latches
return read8(MCP23008_OLAT);
}
void Adafruit_MCP23008::writeGPIO(uint8_t gpio) {
write8(MCP23008_GPIO, gpio);
}
void Adafruit_MCP23008::digitalWrite(uint8_t p, uint8_t d) {
uint8_t gpio;
// only 8 bits!
if (p > 7)
return;
// read the current GPIO output latches
gpio = readGPIO();
// set the pin and direction
if (d == HIGH) {
gpio |= 1 << p;
} else {
gpio &= ~(1 << p);
}
// write the new GPIO
writeGPIO(gpio);
}
void Adafruit_MCP23008::pullUp(uint8_t p, uint8_t d) {
uint8_t gppu;
// only 8 bits!
if (p > 7)
return;
gppu = read8(MCP23008_GPPU);
// set the pin and direction
if (d == HIGH) {
gppu |= 1 << p;
} else {
gppu &= ~(1 << p);
}
// write the new GPIO
write8(MCP23008_GPPU, gppu);
}
uint8_t Adafruit_MCP23008::digitalRead(uint8_t p) {
// only 8 bits!
if (p > 7)
return 0;
// read the current GPIO
return (readGPIO() >> p) & 0x1;
}
uint8_t Adafruit_MCP23008::read8(uint8_t addr) {
Wire.beginTransmission(MCP23008_ADDRESS | i2caddr);
#if ARDUINO >= 100
Wire.write((byte)addr);
#else
Wire.send(addr);
#endif
Wire.endTransmission();
Wire.requestFrom(MCP23008_ADDRESS | i2caddr, 1);
#if ARDUINO >= 100
return Wire.read();
#else
return Wire.receive();
#endif
}
void Adafruit_MCP23008::write8(uint8_t addr, uint8_t data) {
Wire.beginTransmission(MCP23008_ADDRESS | i2caddr);
#if ARDUINO >= 100
Wire.write((byte)addr);
Wire.write((byte)data);
#else
Wire.send(addr);
Wire.send(data);
#endif
Wire.endTransmission();
}
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