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/**
* Copyright (c) 2009 - 2017, Nordic Semiconductor ASA
*
* All rights reserved.
*
* 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, except as embedded into a Nordic
* Semiconductor ASA integrated circuit in a product or a software update for
* such product, 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 Nordic Semiconductor ASA nor the names of its
* contributors may be used to endorse or promote products derived from this
* software without specific prior written permission.
*
* 4. This software, with or without modification, must only be used with a
* Nordic Semiconductor ASA integrated circuit.
*
* 5. Any software provided in binary form under this license must not be reverse
* engineered, decompiled, modified and/or disassembled.
*
* THIS SOFTWARE IS PROVIDED BY NORDIC SEMICONDUCTOR ASA "AS IS" AND ANY EXPRESS
* OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY, NONINFRINGEMENT, AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL NORDIC SEMICONDUCTOR ASA 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.
*
*/
#include <stdint.h>
#include "nrf.h"
#include "nrf_delay.h"
#include "sdio.h"
#include "nrf_gpio.h"
#include "sdio_config.h"
/*lint ++flb "Enter library region" */
/*lint -e717 -save "Suppress do {} while (0) for these macros" */
#define SDIO_CLOCK_HIGH() do { NRF_GPIO->OUTSET = (1UL << SDIO_CONFIG_CLOCK_PIN_NUMBER); } while (0) /*!< Pulls SCL line high */
#define SDIO_CLOCK_LOW() do { NRF_GPIO->OUTCLR = (1UL << SDIO_CONFIG_CLOCK_PIN_NUMBER); } while (0) /*!< Pulls SCL line low */
#define SDIO_DATA_HIGH() do { NRF_GPIO->OUTSET = (1UL << SDIO_CONFIG_DATA_PIN_NUMBER); } while (0) /*!< Pulls SDA line high */
#define SDIO_DATA_LOW() do { NRF_GPIO->OUTCLR = (1UL << SDIO_CONFIG_DATA_PIN_NUMBER); } while (0) /*!< Pulls SDA line low */
#define SDIO_DATA_OUTPUT() do { NRF_GPIO->DIRSET = (1UL << SDIO_CONFIG_DATA_PIN_NUMBER); } while (0) /*!< Configures SDA pin as output */
#define SDIO_CLOCK_OUTPUT() do { NRF_GPIO->DIRSET = (1UL << SDIO_CONFIG_CLOCK_PIN_NUMBER); } while (0) /*!< Configures SCL pin as output */
/*lint -restore */
/*lint -emacro(845,SDIO_DATA_INPUT) // A zero has been given as right argument to operator '|'" */
#define SDIO_DATA_INPUT() do { \
nrf_gpio_cfg_input(25, NRF_GPIO_PIN_NOPULL); \
} while (0)
#define SDIO_DATA_READ() ((NRF_GPIO->IN >> SDIO_CONFIG_DATA_PIN_NUMBER) & 0x1UL) /*!< Reads current state of SDA */
#define SDIO_CLOCK_READ() ((NRF_GPIO->IN >> SDIO_CONFIG_CLOCK_PIN_NUMBER) & 0x1UL) /*!< Reads current state of SCL */
#define SDIO_DELAY() nrf_delay_us(10) /*!< Time to wait when pin states are changed. For fast-mode the delay can be zero and for standard-mode 4 us delay is sufficient. */
void sdio_init(void)
{
SDIO_CLOCK_HIGH();
SDIO_DATA_HIGH();
SDIO_CLOCK_OUTPUT();
SDIO_DATA_INPUT();
// If slave is stuck in the middle of transfer, clock out bits until the slave ACKs the transfer
for (uint_fast8_t i = 16; i--;)
{
SDIO_DELAY();
SDIO_CLOCK_LOW();
SDIO_DELAY();
SDIO_CLOCK_HIGH();
SDIO_DELAY();
if (SDIO_DATA_READ())
{
break;
}
}
for (uint_fast8_t i = 5; i--;)
{
SDIO_DELAY();
SDIO_CLOCK_LOW();
SDIO_DELAY();
SDIO_CLOCK_HIGH();
}
SDIO_DATA_OUTPUT();
SDIO_DATA_HIGH();
SDIO_DELAY();
}
uint8_t sdio_read_byte(uint8_t address)
{
uint8_t data_byte = 0;
SDIO_DATA_OUTPUT();
for (uint_fast8_t i = 8; i--;)
{
SDIO_DELAY();
SDIO_CLOCK_LOW();
if (address & (1U << i))
{
SDIO_DATA_HIGH();
}
else
{
SDIO_DATA_LOW();
}
SDIO_DELAY();
SDIO_CLOCK_HIGH();
}
nrf_delay_us(20);
SDIO_DATA_INPUT();
for (uint_fast8_t i = 8; i--;)
{
SDIO_CLOCK_LOW();
SDIO_DELAY();
SDIO_CLOCK_HIGH();
SDIO_DELAY();
data_byte |= (uint8_t)(SDIO_DATA_READ() << i);
}
SDIO_DATA_HIGH();
SDIO_DATA_OUTPUT();
SDIO_DELAY();
return data_byte;
}
void sdio_read_burst(uint8_t * target_buffer, uint8_t target_buffer_size)
{
uint_fast8_t address = 0x63;
SDIO_DATA_OUTPUT();
for (uint_fast8_t bit_index=8; bit_index--;)
{
SDIO_CLOCK_LOW();
if (address & (1U << bit_index))
{
SDIO_DATA_HIGH();
}
else
{
SDIO_DATA_LOW();
}
SDIO_CLOCK_HIGH();
}
SDIO_DATA_INPUT();
for (uint_fast8_t target_buffer_index = 0; target_buffer_index < target_buffer_size; target_buffer_index++)
{
target_buffer[target_buffer_index] = 0;
for (uint_fast8_t bit_index = 8; bit_index--;)
{
SDIO_CLOCK_LOW();
SDIO_CLOCK_HIGH();
target_buffer[target_buffer_index] |= (uint8_t)(SDIO_DATA_READ() << bit_index);
}
}
}
void sdio_write_byte(uint8_t address, uint8_t data_byte)
{
// Add write indication bit
address |= 0x80;
SDIO_DATA_OUTPUT();
for (uint_fast8_t i = 8; i--;)
{
SDIO_DELAY();
SDIO_CLOCK_LOW();
if (address & (1U << i))
{
SDIO_DATA_HIGH();
}
else
{
SDIO_DATA_LOW();
}
SDIO_DELAY();
SDIO_CLOCK_HIGH();
}
SDIO_DELAY();
for (uint_fast8_t i = 8; i--;)
{
SDIO_CLOCK_LOW();
if (data_byte & (1U << i))
{
SDIO_DATA_HIGH();
}
else
{
SDIO_DATA_LOW();
}
SDIO_DELAY();
SDIO_CLOCK_HIGH();
SDIO_DELAY();
}
SDIO_DATA_HIGH();
SDIO_DELAY();
}
/*lint --flb "Leave library region" */
|
