156 lines
4.3 KiB
C++
156 lines
4.3 KiB
C++
/**
|
|
Copyright (c) 2021 Bosch Sensortec GmbH. All rights reserved.
|
|
|
|
BSD-3-Clause
|
|
|
|
Redistribution and use in source and binary forms, with or without
|
|
modification, are permitted provided that the following conditions are met:
|
|
|
|
1. Redistributions of source code must retain the above copyright
|
|
notice, this list of conditions and the following disclaimer.
|
|
|
|
2. Redistributions in binary form must reproduce the above copyright
|
|
notice, this list of conditions and the following disclaimer in the
|
|
documentation and/or other materials provided with the distribution.
|
|
|
|
3. Neither the name of the copyright holder nor the names of its
|
|
contributors may be used to endorse or promote products derived from
|
|
this software without specific prior written permission.
|
|
|
|
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
|
|
"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
|
|
LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
|
|
FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
|
|
COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
|
|
INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
|
|
(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
|
|
SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
|
HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
|
|
STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
|
|
IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
|
|
POSSIBILITY OF SUCH DAMAGE.
|
|
|
|
@file commMux.cpp
|
|
@date 8 Feb 2022
|
|
@version 1.1.40407
|
|
|
|
*/
|
|
|
|
#include "commMux.h"
|
|
|
|
#define CLOCK_FREQUENCY 400000
|
|
#define COMM_SPEED 8000000
|
|
|
|
const uint8_t I2C_EXPANDER_ADDR = 0x20;
|
|
const uint8_t I2C_EXPANDER_OUTPUT_REG_ADDR = 0x01;
|
|
const uint8_t I2C_EXPANDER_OUTPUT_DESELECT = 0xFF;
|
|
const uint8_t I2C_EXPANDER_CONFIG_REG_ADDR = 0x03;
|
|
const uint8_t I2C_EXPANDER_CONFIG_REG_MASK = 0x00;
|
|
|
|
/**
|
|
* @brief Function to configure the communication across sensors
|
|
*/
|
|
commMux commMuxSetConfig(TwoWire &wireobj, SPIClass &spiobj, uint8_t idx, commMux &comm)
|
|
{
|
|
comm.select = ((0x01 << idx) ^ 0xFF);
|
|
comm.spiobj = &spiobj;
|
|
comm.wireobj = &wireobj;
|
|
|
|
return comm;
|
|
}
|
|
|
|
/**
|
|
* @brief Function to trigger the communication
|
|
*/
|
|
void commMuxBegin(TwoWire &wireobj, SPIClass &spiobj)
|
|
{
|
|
wireobj.begin();
|
|
wireobj.setClock(CLOCK_FREQUENCY);
|
|
wireobj.beginTransmission(I2C_EXPANDER_ADDR);
|
|
wireobj.write(I2C_EXPANDER_CONFIG_REG_ADDR);
|
|
wireobj.write(I2C_EXPANDER_CONFIG_REG_MASK);
|
|
wireobj.endTransmission();
|
|
|
|
spiobj.begin();
|
|
}
|
|
|
|
/**
|
|
* @brief Function to set the ship select pin of the SPI
|
|
*/
|
|
static void setChipSelect(TwoWire *wireobj, uint8_t mask)
|
|
{
|
|
// send I2C-Expander device address
|
|
wireobj->beginTransmission(I2C_EXPANDER_ADDR);
|
|
// send I2C-Expander output register address
|
|
wireobj->write(I2C_EXPANDER_OUTPUT_REG_ADDR);
|
|
// send mask to set output level of GPIO pins
|
|
wireobj->write(mask);
|
|
// end communication
|
|
wireobj->endTransmission();
|
|
}
|
|
|
|
/**
|
|
* @brief Function to write the sensor data to the register
|
|
*/
|
|
int8_t commMuxWrite(uint8_t reg_addr, const uint8_t *reg_data, uint32_t length, void *intf_ptr)
|
|
{
|
|
commMux *comm = (commMux*) intf_ptr;
|
|
uint32_t i;
|
|
|
|
if (comm)
|
|
{
|
|
setChipSelect(comm->wireobj, comm->select);
|
|
|
|
comm->spiobj->beginTransaction(SPISettings(COMM_SPEED, MSBFIRST, SPI_MODE0));
|
|
comm->spiobj->transfer(reg_addr);
|
|
for (i = 0; i < length; i++)
|
|
{
|
|
comm->spiobj->transfer(reg_data[i]);
|
|
}
|
|
comm->spiobj->endTransaction();
|
|
|
|
setChipSelect(comm->wireobj, I2C_EXPANDER_OUTPUT_DESELECT);
|
|
|
|
return 0;
|
|
}
|
|
|
|
return 1;
|
|
}
|
|
|
|
/**
|
|
* @brief Function to read the sensor data from the register
|
|
*/
|
|
int8_t commMuxRead(uint8_t reg_addr, uint8_t *reg_data, uint32_t length, void *intf_ptr)
|
|
{
|
|
commMux *comm = (commMux*) intf_ptr;
|
|
uint32_t i;
|
|
|
|
if (comm)
|
|
{
|
|
setChipSelect(comm->wireobj, comm->select);
|
|
|
|
comm->spiobj->beginTransaction(SPISettings(COMM_SPEED, MSBFIRST, SPI_MODE0));
|
|
comm->spiobj->transfer(reg_addr);
|
|
for (i = 0; i < length; i++)
|
|
{
|
|
reg_data[i] = comm->spiobj->transfer(0xFF);
|
|
}
|
|
comm->spiobj->endTransaction();
|
|
|
|
setChipSelect(comm->wireobj, I2C_EXPANDER_OUTPUT_DESELECT);
|
|
|
|
return 0;
|
|
}
|
|
|
|
return 1;
|
|
}
|
|
|
|
/**
|
|
* @brief Function to maintain a delay between communication
|
|
*/
|
|
void commMuxDelay(uint32_t period_us, void *intf_ptr)
|
|
{
|
|
(void) intf_ptr;
|
|
delayMicroseconds(period_us);
|
|
}
|