mcp23x08.h

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/*
 * mcp23x17:
 *  Copyright (c) 2012-2013 Gordon Henderson
 *
 *  Header file for code using the MCP23x17 GPIO expander chip.
 *  This comes in 2 flavours: MCP23017 which has an I2C interface,
 *  an the MXP23S17 which has an SPI interface.
 ***********************************************************************
 * This file is part of wiringPi:
 *  https://projects.drogon.net/raspberry-pi/wiringpi/
 *
 *    wiringPi is free software: you can redistribute it and/or modify
 *    it under the terms of the GNU Lesser General Public License as
 *    published by the Free Software Foundation, either version 3 of the
 *    License, or (at your option) any later version.
 *
 *    wiringPi is distributed in the hope that it will be useful,
 *    but WITHOUT ANY WARRANTY; without even the implied warranty of
 *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *    GNU Lesser General Public License for more details.
 *
 *    You should have received a copy of the GNU Lesser General Public
 *    License along with wiringPi.
 *    If not, see <http://www.gnu.org/licenses/>.
 ***********************************************************************
 */


// MCP23x17 Registers

#define IODIRA      0x00
#define IPOLA       0x02
#define GPINTENA    0x04
#define DEFVALA     0x06
#define INTCONA     0x08
#define IOCON       0x0A
#define GPPUA       0x0C
#define INTFA       0x0E
#define INTCAPA     0x10
#define GPIOA       0x12
#define OLATA       0x14

#define IODIRB      0x01
#define IPOLB       0x03
#define GPINTENB    0x05
#define DEFVALB     0x07
#define INTCONB     0x09
#define IOCONB      0x0B
#define GPPUB       0x0D
#define INTFB       0x0F
#define INTCAPB     0x11
#define GPIOB       0x13
#define OLATB       0x15

// Bits in the IOCON register

#define IOCON_UNUSED    0x01
#define IOCON_INTPOL    0x02
#define IOCON_ODR   0x04
#define IOCON_HAEN  0x08
#define IOCON_DISSLW    0x10
#define IOCON_SEQOP 0x20
#define IOCON_MIRROR    0x40
#define IOCON_BANK_MODE 0x80

// Default initialisation mode

#define IOCON_INIT  (IOCON_SEQOP)

// SPI Command codes

#define CMD_WRITE   0x40
#define CMD_READ    0x41