File content as of revision 2:1d5204d29bc5:

/**************************************************************************//**
 * @file     mcp23s08.cpp
 * @brief    Base class for wrapping the interface with the GPIO Extender .
 * @version: V1.0
 * @date:    9/17/2019

 *
 * @note
 * This is Third party software adapted to the ESCM project.  
 * See copyright below.
 *
 * @par
 * E3 Designers LLC is supplying this software for use with Cortex-M3 LPC1768
 * processor based microcontroller for the ESCM 2000 Monitor and Display.  
 *  *
 * @par
 * THIS SOFTWARE IS PROVIDED "AS IS".  NO WARRANTIES, WHETHER EXPRESS, IMPLIED
 * OR STATUTORY, INCLUDING, BUT NOT LIMITED TO, IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE APPLY TO THIS SOFTWARE.
 * ARM SHALL NOT, IN ANY CIRCUMSTANCES, BE LIABLE FOR SPECIAL, INCIDENTAL, OR
 * CONSEQUENTIAL DAMAGES, FOR ANY REASON WHATSOEVER.
 *
 ******************************************************************************/
 
 /*
 ___  _   _  _ __ ___    ___  | |_  ___   _   _ 
/ __|| | | || '_ ` _ \  / _ \ | __|/ _ \ | | | |
\__ \| |_| || | | | | || (_) || |_| (_) || |_| |
|___/ \__,_||_| |_| |_| \___/  \__|\___/  \__, |
                                          |___/ 
                                          
    gpio_expander - An attemp to create a fast and universal library for drive many GPIO chips
    
model:          company:        pins:       protocol:       Special Features:
---------------------------------------------------------------------------------------------------------------------
mcp23s08        Microchip         8         SPI                 INT/HAEN
---------------------------------------------------------------------------------------------------------------------
Version history:
0.5b1: first release, just coded and never tested
0.5b2: fixed 2wire version, added portPullup, tested output mode (ok)
0.5b3: added some drivers
0.5b4: ability to include library inside other libraries.
0.5b7: Changed functionalities of some function.
0.6b1: Changed gpioRegisterRead to gpioRegisterReadByte. Added gpioRegisterReadWord (for some GPIO)
0.6b3: Added basic support for SPI transactions, small optimizations.
0.8b3: Added 2 more commands and 2 gpio chip.
0.8b4: Support for SPI Transaction post setup
---------------------------------------------------------------------------------------------------------------------
        Copyright (c) 2013-2014, s.u.m.o.t.o.y [sumotoy(at)gmail.com]
---------------------------------------------------------------------------------------------------------------------
    gpio_expander Library is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.
    gpio_expander Library 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 General Public License for more details.
    You should have received a copy of the GNU General Public License
    along with Foobar.  If not, see <http://www.gnu.org/licenses/>.
    
    +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
    Version:0.8b3: Added 2 more commands and 2 gpio chip.
    +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
*/

/* ------------------------------ MCP23S08 WIRING ------------------------------------
This chip has a very useful feature called HAEN that allow you to share the same CS pin trough
4 different addresses. Of course chip has to be Microchip and should be assigned to different addresses!
Basic Address:  001000 A1 A0 (from 0x20 to 0x23)
A1,A0 tied to ground = 0x20
                __ __
    ->  sck   [|  U  |] ++++
    ->  mosi  [|     |] IO-7
    <-  miso  [|     |] IO-6
        A1    [|     |] IO-5
        A0    [|     |] IO-4
 rst (con.+)  [|     |] IO-3
        cs    [|     |] IO-2
        int   [|     |] IO-1
        GND   [|_____|] IO-0
*/
#ifndef _MCP23S08_H_
#define _MCP23S08_H_

#include <inttypes.h>

class mcp23s08 : public SPI 
{

public:
    mcp23s08(PinName mosi, PinName miso, PinName clk, PinName cs_pin,const uint8_t haenAdrs);
    void            postSetup(const uint8_t haenAdrs);//used with other libraries only
    virtual void    begin(bool protocolInitOverride=false); //protocolInitOverride=true will not init the SPI   

    
    void            gpioPinMode(uint8_t mode);                      //set all pins to INPUT or OUTPUT
    void            gpioPinMode(uint8_t pin, bool mode);        //set a unique pin as IN(1) or OUT (0)
    void            gpioPort(uint8_t value);                    //write data to all pins
    //void          gpioPort(uint8_t lowByte, uint8_t highByte);        //same as abowe but uses 2 separate bytes (not applicable to this chip)
    uint8_t         readGpioPort();                             //read the state of the pins (all)
    uint8_t         readGpioPortFast();                         
    
    void            gpioDigitalWrite(uint8_t pin, bool value);  //write data to one pin
    void            gpioDigitalWriteFast(uint8_t pin, bool value);
    int             gpioDigitalRead(uint8_t pin);               //read data from one pin
    uint8_t         gpioRegisterReadByte(uint8_t reg);                  //read a uint8_t from chip register
    int             gpioDigitalReadFast(uint8_t pin);
    void            gpioRegisterWriteByte(uint8_t reg,uint8_t data);        //write a chip register
    void            portPullup(uint8_t data);                       // true=pullup, false=pulldown all pins
    void            gpioPortUpdate();
    // direct access commands
    uint8_t         readAddress(uint8_t addr);
    
    void            setSPIspeed(uint32_t spispeed);//for SPI transactions
    
    //------------------------- REGISTERS
    uint8_t IOCON;
    uint8_t IODIR;
    uint8_t GPPU;
    uint8_t GPIO;
    uint8_t GPINTEN;
    uint8_t IPOL;
    uint8_t DEFVAL;
    uint8_t INTF;
    uint8_t INTCAP;
    uint8_t OLAT;
    uint8_t INTCON;
    
private:
    DigitalOut cs;

    uint8_t         _cs;
    uint8_t         _adrs;
    
    uint32_t        _spiTransactionsSpeed;//for SPI transactions
    
    uint8_t         _useHaen;
    uint8_t         _readCmd;
    uint8_t         _writeCmd;
    void            startSend(bool mode);
    void            endSend();
    uint8_t         _gpioDirection;
    uint8_t         _gpioState;
    void            writeByte(uint8_t addr, uint8_t data);  
};
#endif