97 lines
2.7 KiB
C
97 lines
2.7 KiB
C
|
/**
|
||
|
|
* \file
|
||
|
|
* <!--
|
||
|
|
* This file is part of BeRTOS.
|
||
|
|
*
|
||
|
|
* Bertos 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 2 of the License, or
|
||
|
|
* (at your option) any later version.
|
||
|
|
*
|
||
|
|
* This program 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 this program; if not, write to the Free Software
|
||
|
|
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
|
||
|
|
*
|
||
|
|
* As a special exception, you may use this file as part of a free software
|
||
|
|
* library without restriction. Specifically, if other files instantiate
|
||
|
|
* templates or use macros or inline functions from this file, or you compile
|
||
|
|
* this file and link it with other files to produce an executable, this
|
||
|
|
* file does not by itself cause the resulting executable to be covered by
|
||
|
|
* the GNU General Public License. This exception does not however
|
||
|
|
* invalidate any other reasons why the executable file might be covered by
|
||
|
|
* the GNU General Public License.
|
||
|
|
*
|
||
|
|
* Copyright 2007 Develer S.r.l. (http://www.develer.com/)
|
||
|
|
*
|
||
|
|
* -->
|
||
|
|
*
|
||
|
|
* \brief PCF8574 i2c port expander driver.
|
||
|
|
*
|
||
|
|
* This driver controls the PCF8574.
|
||
|
|
* The PCF8574 is an 8bit i2c port expander.
|
||
|
|
* You can read/write 8 pins through an i2c bus.
|
||
|
|
* The pins are quasi-bidirectionals, this mean that
|
||
|
|
* without the need of a direction register you can use
|
||
|
|
* each pin as input or output, see datasheet on how this
|
||
|
|
* is achieved.
|
||
|
|
*
|
||
|
|
* \author Francesco Sacchi <batt@develer.com>
|
||
|
|
*/
|
||
|
|
|
||
|
|
#include "pcf8574.h"
|
||
|
|
|
||
|
|
#include "cfg/cfg_i2c.h"
|
||
|
|
|
||
|
|
#include <cfg/module.h>
|
||
|
|
|
||
|
|
#include <drv/i2c.h>
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Read PCF8574 \a pcf bit status.
|
||
|
|
* \return the pins status or EOF on errors.
|
||
|
|
*/
|
||
|
|
int pcf8574_get_2(I2c *i2c, Pcf8574 *pcf)
|
||
|
|
{
|
||
|
|
i2c_start_r(i2c, PCF8574ID | ((pcf->addr << 1) & 0xF7), 1, I2C_STOP);
|
||
|
|
|
||
|
|
int data = i2c_getc(i2c);
|
||
|
|
|
||
|
|
if (i2c_error(i2c))
|
||
|
|
data = EOF;
|
||
|
|
|
||
|
|
return data;
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Write to PCF8574 \a pcf port \a data.
|
||
|
|
* \return true if ok, false on errors.
|
||
|
|
*/
|
||
|
|
bool pcf8574_put_3(I2c *i2c, Pcf8574 *pcf, uint8_t data)
|
||
|
|
{
|
||
|
|
i2c_start_w(i2c, PCF8574ID | ((pcf->addr << 1) & 0xF7), 1, I2C_STOP);
|
||
|
|
i2c_putc(i2c, data);
|
||
|
|
|
||
|
|
if (i2c_error(i2c))
|
||
|
|
return false;
|
||
|
|
|
||
|
|
return true;
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Init a PCF8574 on the bus with addr \a addr.
|
||
|
|
* \return true if device is found, false otherwise.
|
||
|
|
*/
|
||
|
|
bool pcf8574_init_3(I2c *i2c, Pcf8574 *pcf, pcf8574_addr addr)
|
||
|
|
{
|
||
|
|
ASSERT(i2c);
|
||
|
|
pcf->addr = addr;
|
||
|
|
|
||
|
|
return (pcf8574_get(i2c, pcf) != EOF);
|
||
|
|
}
|
||
|
|
|