sci_datalink.c File Reference

#include "sci_cmd.h"
#include "sci_datalink.h"
#include "sci_byte_stuffing.h"
#include "sci_crc8.h"
#include "sci_handshaking.h"
#include "driver/irq.h"
#include "debug.h"
#include "driver/uart.h"
#include <stddef.h>
#include <assert.h>
#include "utility/time.h"

Include dependency graph for sci_datalink.c:

Macros
#define	AFBR_SCI_USB   0
	SCI Layer 2: Data Link and Data Frame Module.

Functions
static void	RaiseError (status_t error)
static void	RxCallback (uint8_t const *data, uint32_t size)
static void	TxCallback (status_t status, sci_frame_t *frame)
static sci_frame_t *	SCI_DataLink_RequestFrame (sci_frame_queue_t *queue)
static status_t	SCI_DataLink_SendFrame (sci_frame_t *frame)
static void	SCI_DataLink_ReleaseFrame (sci_frame_t *frame)
static uint8_t	SCI_DataLink_GetCRC (sci_frame_t const *frame)
static uint8_t	SCI_DataLink_CalcCRC (sci_frame_t const *frame)
static void	SCI_Frame_QueueCRC (sci_frame_t *frame)
	Inserts a checksum into the Tx frame;.
status_t	SCI_DataLink_Init (void)
	Initialize the data link module.
status_t	SCI_DataLink_CheckRxFrame (sci_frame_t *frame)
	Checks the CRC checksum for a RX frame.
void	SCI_DataLink_ReleaseFrames (sci_frame_t *frame)
	Releases the frame queue.
void	SCI_DataLink_ResetRxFrames (sci_frame_t *frame)
	Resets the frame read pointer to the very first byte (= command byte).
sci_frame_t *	SCI_DataLink_RequestTxFrame (bool queueStartByte)
	Find an unused TX buffer from the queue and prepare it with a start byte.
bool	SCI_DataLink_IsTxBusy (void)
	Returns whether the TX line is currently busy and data is being sent.
status_t	SCI_DataLink_SendTxFrame (sci_frame_t *frame, bool high_priority)
	Trigger the data transfer and releases the TX buffers.

Variables
static uint8_t	SCI_DataBuffer [SCI_FRAME_SIZE *SCI_FRAME_BUF_CT] = { 0 }
static sci_frame_t	SCI_FrameBuffer [SCI_FRAME_BUF_CT]
static sci_frame_queue_t	SCI_RxFrameQueue
static sci_frame_queue_t	SCI_TxFrameQueue
sci_rx_cmd_cb_t	SCI_RxCallback = 0
sci_error_cb_t	SCI_ErrorCallback = 0
static volatile sci_frame_t *	SCI_CurrentTxFrame = 0

Macro Definition Documentation

AFBR_SCI_USB

#define AFBR_SCI_USB   0

SCI Layer 2: Data Link and Data Frame Module.

This file provides a data link layer for the systems communication interface. It also contains the implementation of the data frame interface.

Copyright

Copyright (c) 2023, Broadcom Inc. 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 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.

Preprocessor flag to choose between USB and non-USB (UART) connection.

Function Documentation

RaiseError()

static void RaiseError ( status_t  error )

inlinestatic

RxCallback()

static void RxCallback ( uint8_t const *  data, uint32_t  size  )

static

< Flag for byte stuffing

< the current buffer in the queue.

< the first buffer in the queue.

SCI_DataLink_CalcCRC()

static uint8_t SCI_DataLink_CalcCRC ( sci_frame_t const *  frame )

static

SCI_DataLink_GetCRC()

static uint8_t SCI_DataLink_GetCRC ( sci_frame_t const *  frame )

static

SCI_DataLink_ReleaseFrame()

static void SCI_DataLink_ReleaseFrame ( sci_frame_t *  frame )

inlinestatic

SCI_DataLink_RequestFrame()

static sci_frame_t * SCI_DataLink_RequestFrame ( sci_frame_queue_t *  queue )

static

SCI_DataLink_SendFrame()

static status_t SCI_DataLink_SendFrame ( sci_frame_t *  frame )

inlinestatic

SCI_Frame_QueueCRC()

static void SCI_Frame_QueueCRC ( sci_frame_t *  frame )

static

Inserts a checksum into the Tx frame;.

---

Given a Tx frame with data filled, this function calculates and appends the CRC to the frame buffer. It assumes that the first byte in the TX buffer is start byte which is usually ensured by the SCI_DataLink_RequestTxFrame function.

Parameters

frame

The frame for which a checksum is calculated.

TxCallback()

static void TxCallback ( status_t  status, sci_frame_t *  frame  )

static

Variable Documentation

SCI_CurrentTxFrame

volatile sci_frame_t* SCI_CurrentTxFrame = 0

static

A pointer to the frame that is currently sent. It is used to enqueue more frames if the UART is busy.

SCI_DataBuffer

uint8_t SCI_DataBuffer[SCI_FRAME_SIZE *SCI_FRAME_BUF_CT] = { 0 }

static

The data buffer for rx and tx frames.

SCI_ErrorCallback

sci_error_cb_t SCI_ErrorCallback = 0

Callback function pointer for error event.

SCI_FrameBuffer

sci_frame_t SCI_FrameBuffer[SCI_FRAME_BUF_CT]

static

The frame buffer for rx and tx frames.

SCI_RxCallback

sci_rx_cmd_cb_t SCI_RxCallback = 0

Callback function pointer for received frame event.

SCI_RxFrameQueue

sci_frame_queue_t SCI_RxFrameQueue

static

The data frame queue for rx frames.

SCI_TxFrameQueue

sci_frame_queue_t SCI_TxFrameQueue

static

The data frame queue for tx frames.