uart_ow.h

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/*
 * Author: Jon Trulson <jtrulson@ics.com>
 * Copyright (c) 2016 Intel Corporation
 *
 * 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 THE AUTHORS OR COPYRIGHT HOLDERS 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.
 */

#pragma once

#ifdef __cplusplus
extern "C" {
#endif

#include <stdio.h>

#include "common.h"
#include "uart.h"

/* for now, we simply use the normal MRAA UART context */
typedef struct _mraa_uart_ow {
    mraa_uart_context uart;
    /* search state */
    unsigned char ROM_NO[8]; /* 8 byte (64b) rom code */
    int LastDiscrepancy;
    int LastFamilyDiscrepancy;
    mraa_boolean_t LastDeviceFlag;
} *mraa_uart_ow_context;

/* 8 bytes (64 bits) for a device rom code */
static const int MRAA_UART_OW_ROMCODE_SIZE = 8;

typedef enum {
    MRAA_UART_OW_CMD_READ_ROM = 0x33,         
    MRAA_UART_OW_CMD_MATCH_ROM = 0x55,        
    MRAA_UART_OW_CMD_SKIP_ROM = 0xcc,         
    MRAA_UART_OW_CMD_SEARCH_ROM_ALARM = 0xec, 
    MRAA_UART_OW_CMD_SEARCH_ROM = 0xf0        
} mraa_uart_ow_rom_cmd_t;

mraa_uart_ow_context mraa_uart_ow_init(int uart);

mraa_uart_ow_context mraa_uart_ow_init_raw(const char* path);

const char* mraa_uart_ow_get_dev_path(mraa_uart_ow_context dev);

mraa_result_t mraa_uart_ow_stop(mraa_uart_ow_context dev);

int mraa_uart_ow_read_byte(mraa_uart_ow_context dev);

int mraa_uart_ow_write_byte(mraa_uart_ow_context dev, uint8_t byte);

int mraa_uart_ow_bit(mraa_uart_ow_context dev, uint8_t bit);

mraa_result_t mraa_uart_ow_reset(mraa_uart_ow_context dev);

mraa_result_t mraa_uart_ow_rom_search(mraa_uart_ow_context dev, mraa_boolean_t start, uint8_t* id);

mraa_result_t mraa_uart_ow_command(mraa_uart_ow_context dev, uint8_t command, uint8_t* id);

uint8_t mraa_uart_ow_crc8(uint8_t* buffer, uint16_t length);

#ifdef __cplusplus
}
#endif