tap_esc_common.h

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/*
 * tap_esc_common.h
 *
 */

#pragma once

#include <stdint.h>

#include "drv_tap_esc.h"

namespace tap_esc_common
{
/**
 *  Select tap esc responder data for serial interface by 74hct151. GPIOs to be
 *  defined in board_config.h
 *  @param sel ID of the ESC (responder) of which feedback is requested
 */
void select_responder(uint8_t sel);

/**
 *  Opens a device for use as UART.
 *  @param device UNIX path of UART device
 *  @param uart_fd file-descriptor of UART device
 *  @return 0 on success, -1 on error
 */
int initialise_uart(const char *const device, int &uart_fd);

/**
 *  Closes a device previously opened with initialise_uart().
 *  @param uart_fd file-descriptor of UART device as provided by initialise_uart()
 *  @return 0 on success, -1 on error
 */
int deinitialise_uart(int &uart_fd);

/**
 *  Enables/disables flow control for open UART device.
 *  @param uart_fd file-descriptor of UART device
 *  @param enabled Set true for enabling and false for disabling flow control
 *  @return 0 on success, -1 on error
 */
int enable_flow_control(int uart_fd, bool enabled);

/**
 *  Sends a packet to all ESCs and requests a specific ESC to respond
 *  @param uart_fd file-descriptor of UART device
 *  @param packet Packet to be sent to ESCs. CRC information will be added.
 *  @param responder ID of the ESC (responder) that should return feedback
 *  @return On success number of bytes written, on error -1
 */
int send_packet(int uart_fd, EscPacket &packet, int responder);

/**
 *  Read data from the UART into a buffer
 *  @param uart_fd file-descriptor of UART device
 *  @param uart_buf Buffer where incoming data will be stored
 *  @return 0 on success, -1 on error
 */
int read_data_from_uart(int uart_fd, ESC_UART_BUF *const uart_buf);

/**
 *  Parse feedback from an ESC
 *  @param serial_buf Buffer where incoming data will be stored
 *  @param packetdata Packet that will be populated with information from buffer
 *  @return 0 on success, -1 on error
 */
int parse_tap_esc_feedback(ESC_UART_BUF *const serial_buf, EscPacket *const packetdata);

/**
 *  Lookup-table for faster CRC computation when sending ESC packets.
 */
extern const uint8_t crc_table[];
} /* tap_esc_common */