Library for MAX7300 GPIO Expander
max7300.cpp
- Committer:
- j3
- Date:
- 2015-07-16
- Revision:
- 1:e1ee2549a047
- Parent:
- 0:350a850a7191
- Child:
- 3:e044960e516c
File content as of revision 1:e1ee2549a047:
/******************************************************************//**
* @file max7300.h
*
* @author Justin Jordan
*
* @version 0.0
*
* Started: 14JUL15
*
* Updated:
*
* @brief Source file for Max7300 class
***********************************************************************
* Copyright (C) 2015 Maxim Integrated Products, Inc., All Rights Reserved.
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included
* in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
* OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
* IN NO EVENT SHALL MAXIM INTEGRATED BE LIABLE FOR ANY CLAIM, DAMAGES
* OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
* ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
* OTHER DEALINGS IN THE SOFTWARE.
*
* Except as contained in this notice, the name of Maxim Integrated
* Products, Inc. shall not be used except as stated in the Maxim Integrated
* Products, Inc. Branding Policy.
*
* The mere transfer of this software does not imply any licenses
* of trade secrets, proprietary technology, copyrights, patents,
* trademarks, maskwork rights, or any other form of intellectual
* property whatsoever. Maxim Integrated Products, Inc. retains all
* ownership rights.
**********************************************************************/
#include "max7300.h"
//configuration register bits
#define MAX7300_S_BIT 0x01
#define MAX7300_M_BIT 0x80
//registers
#define MAX7300_CONFIGURATION 0x04
#define MAX7300_TRANSITION_DETECT_MASK 0x06
#define MAX7300_PORT_CONFIGURATION 0x09
#define MAX7300_PORT_ONLY_BASE_ADRS 0x20
//helper for calclating register addresses in 8 port wide fxs
#define MAX7300_8_PORTS_OFFSET 0x40
//*********************************************************************
Max7300::Max7300(I2C *i2c_bus, max7300_i2c_adrs_t i2c_adrs): _p_i2c(i2c_bus)
{
_i2c_owner = false;
_r_adrs = ((i2c_adrs << 1) | 1);
_w_adrs = (i2c_adrs << 1);
}
//*********************************************************************
Max7300::Max7300(PinName sda, PinName scl, max7300_i2c_adrs_t i2c_adrs)
{
_p_i2c = new I2C(sda, scl);
_i2c_owner = true;
_r_adrs = ((i2c_adrs << 1) | 1);
_w_adrs = (i2c_adrs << 1);
}
//*********************************************************************
Max7300::~Max7300()
{
if(_i2c_owner)
{
delete _p_i2c;
}
}
//*********************************************************************
int16_t Max7300::enable_ports(void)
{
int16_t result = -1;
result = write_config_register(true, MAX7300_S_BIT);
return result;
}
//*********************************************************************
int16_t Max7300::disable_ports(void)
{
int16_t result = -1;
result = write_config_register(false, MAX7300_S_BIT);
return result;
}
//*********************************************************************
int16_t Max7300::enable_transition_detection(void)
{
int16_t result = -1;
result = write_config_register(true, MAX7300_M_BIT);
return result;
}
//*********************************************************************
int16_t Max7300::disable_transition_detection(void)
{
int16_t result = -1;
result = write_config_register(false, MAX7300_M_BIT);
return result;
}
//*********************************************************************
int16_t Max7300::config_port(max7300_port_number_t port_num, max7300_port_type_t port_type)
{
int16_t result = -1;
char data[2];
uint8_t cnt = 0;
//get address of port configuration register
data[cnt++] = ((port_num/4) + 8);
//get port config bits offset in that register
uint8_t offset = (port_num % 4);
//set internal register pointer to port configuration register
result = _p_i2c->write(_w_adrs, data, 1, true);
if(!result)
{
//get current port configuration register
result = _p_i2c->read(_w_adrs, (data + 1), 1, true);
if(!result)
{
//clear old port configuration, do not increment count
data[cnt] &= ~(0x03 << (offset*2));
//set port configuration bits
data[cnt++] |= ((port_type & 0x03) << (offset*2));
//write back to device
result = _p_i2c->write(_w_adrs, data, cnt, false);
}
}
return result;
}
//*********************************************************************
int16_t Max7300::config_4_ports(max7300_port_number_t low_port, uint8_t data)
{
int16_t result = -1;
char local_data[2];
uint8_t cnt = 0;
if(low_port <= MAX7300_PORT_28)
{
if((low_port % 4) == 0)
{
local_data[cnt++] = ((low_port/4) + 8);
local_data[cnt++] = data;
//no need for read, modify, write.
//Fx is intended to write whole register
result = _p_i2c->write(_w_adrs, local_data, cnt, false);
}
}
return result;
}
//*********************************************************************
int16_t Max7300::config_all_ports(max7300_port_type_t port_type)
{
int16_t result = -1;
char data[8];
char local_type = 0;
uint8_t cnt = 0;
//build byte for each port configuration register
local_type = ((port_type << 6) | (port_type << 4) | (port_type << 2) | port_type);
//stuff packet
data[cnt++] = MAX7300_PORT_CONFIGURATION;
for(/**/;cnt < 8; cnt++)
{
data[cnt] = local_type;
}
result = _p_i2c->write(_w_adrs, data, cnt, false);
return result;
}
//*********************************************************************
int16_t Max7300::read_port(max7300_port_number_t port_num)
{
int16_t result = -1;
char data[2];
data[0] = (port_num + MAX7300_PORT_ONLY_BASE_ADRS);
//set internal register pointer to port data register
result = _p_i2c->write(_w_adrs, data, 1, true);
if(!result)
{
//get port data
result = _p_i2c->read(_w_adrs, (data + 1), 1, false);
if(!result)
{
result = data[1];
}
else
{
result = -1;
}
}
return result;
}
//*********************************************************************
int16_t Max7300::write_port(max7300_port_number_t port_num, uint8_t data)
{
int16_t result = -1;
char local_data[2];
uint8_t cnt = 0;
local_data[cnt++] = (port_num + MAX7300_PORT_ONLY_BASE_ADRS);
local_data[cnt++] = data;
//no need for read, modify, write.
//Fx is intended to write whole register
result = _p_i2c->write(_w_adrs, local_data, cnt, false);
return result;
}
//*********************************************************************
int16_t Max7300::read_8_ports(max7300_port_number_t low_port)
{
int16_t result = -1;
char data[2];
if((low_port >= MAX7300_PORT_04) && (low_port <= MAX7300_PORT_24))
{
data[0] = low_port + MAX7300_8_PORTS_OFFSET;
//set internal register pointer to port data register
result = _p_i2c->write(_w_adrs, data, 1, true);
if(!result)
{
//get port data
result = _p_i2c->read(_w_adrs, (data + 1), 1, false);
if(!result)
{
result = data[1];
}
else
{
result = -1;
}
}
}
return result;
}
//*********************************************************************
int16_t Max7300::write_8_ports(max7300_port_number_t low_port, uint8_t data)
{
int16_t result = -1;
char local_data[2];
uint8_t cnt = 0;
if(low_port <= MAX7300_PORT_24)
{
local_data[cnt++] = low_port + MAX7300_8_PORTS_OFFSET;
local_data[cnt++] = data;
//no need for read, modify, write.
//Fx is intended to write whole register
result = _p_i2c->write(_w_adrs, local_data, cnt, false);
}
return result;
}
//*********************************************************************
int16_t Max7300::read_mask_register(bool enable_snapshot)
{
int16_t result = -1;
char data[2];
data[0] = MAX7300_TRANSITION_DETECT_MASK;
//set internal register pointer to mask register
result = _p_i2c->write(_w_adrs, data, 1, true);
if(!result)
{
//get mask data
result = _p_i2c->read(_w_adrs, (data + 1), 1, false);
if(!result)
{
if(enable_snapshot)
{
result = enable_transition_detection();
if(!result)
{
result = data[1];
}
else
{
result = -1;
}
}
else
{
result = data[1];
}
}
else
{
result = -1;
}
}
return result;
}
//*********************************************************************
int16_t Max7300::write_mask_register(uint8_t data)
{
int16_t result = -1;
char local_data[2];
uint8_t cnt = 0;
local_data[cnt++] = MAX7300_TRANSITION_DETECT_MASK;
local_data[cnt++] = data;
//no need for read, modify, write.
//Fx is intended to write whole register
result = _p_i2c->write(_w_adrs, local_data, cnt, false);
return result;
}
//*********************************************************************
int16_t Max7300::write_config_register(bool set_clear, uint8_t data)
{
int16_t result = -1;
char local_data[2];
uint8_t cnt = 0;
local_data[cnt++] = MAX7300_CONFIGURATION;
//set internal register pointer to configuration register
result = _p_i2c->write(_w_adrs, local_data, 1, true);
if(!result)
{
//get current configuration register
result = _p_i2c->read(_w_adrs, (local_data + 1), 1, true);
if(!result)
{
if(set_clear)
{
local_data[cnt++] |= data;
}
else
{
local_data[cnt++] &= ~data;
}
//write back to device
result = _p_i2c->write(_w_adrs, local_data, cnt, false);
}
}
return result;
}