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2023-12-10 15:30:06 +01:00

70 lines
2.4 KiB
C

/*
* SPDX-FileCopyrightText: 2021-2023 Espressif Systems (Shanghai) CO LTD
*
* SPDX-License-Identifier: Apache-2.0
*/
#pragma once
#include "mb_config.h"
#ifdef __cplusplus
extern "C" {
#endif
/*!
* Constants which defines the format of a modbus frame. The example is
* shown for a Modbus RTU/ASCII frame. Note that the Modbus PDU is not
* dependent on the underlying transport.
*
* <code>
* <------------------------ MODBUS SERIAL LINE PDU (1) ------------------->
* <----------- MODBUS PDU (1') ---------------->
* +-----------+---------------+----------------------------+-------------+
* | Address | Function Code | Data | CRC/LRC |
* +-----------+---------------+----------------------------+-------------+
* | | | |
* (2) (3/2') (3') (4)
*
* (1) ... MB_SER_PDU_SIZE_MAX = 256
* (2) ... MB_SER_PDU_ADDR_OFF = 0
* (3) ... MB_SER_PDU_PDU_OFF = 1
* (4) ... MB_SER_PDU_SIZE_CRC = 2
*
* (1') ... MB_PDU_SIZE_MAX = 253
* (2') ... MB_PDU_FUNC_OFF = 0
* (3') ... MB_PDU_DATA_OFF = 1
* </code>
*/
/* ----------------------- Defines ------------------------------------------*/
#define MB_PDU_SIZE_MAX 253 /*!< Maximum size of a PDU. */
#define MB_PDU_SIZE_MIN 1 /*!< Function Code */
#define MB_PDU_FUNC_OFF 0 /*!< Offset of function code in PDU. */
#define MB_PDU_DATA_OFF 1 /*!< Offset for response data in PDU. */
#define MB_SER_PDU_SIZE_MAX MB_BUFFER_SIZE /*!< Maximum size of a Modbus frame. */
#define MB_SER_PDU_SIZE_LRC 1 /*!< Size of LRC field in PDU. */
#define MB_SER_PDU_ADDR_OFF 0 /*!< Offset of slave address in Ser-PDU. */
#define MB_SER_PDU_PDU_OFF 1 /*!< Offset of Modbus-PDU in Ser-PDU. */
#define MB_SER_PDU_SIZE_CRC 2 /*!< Size of CRC field in PDU. */
#define MB_TCP_TID 0
#define MB_TCP_PID 2
#define MB_TCP_LEN 4
#define MB_TCP_UID 6
#define MB_TCP_FUNC 7
#if MB_MASTER_TCP_ENABLED
#define MB_SEND_BUF_PDU_OFF MB_TCP_FUNC
#else
#define MB_SEND_BUF_PDU_OFF MB_SER_PDU_PDU_OFF
#endif
#define MB_TCP_BUFF_MAX_SIZE MB_TCP_FUNC + MB_PDU_SIZE_MAX
#define MB_TCP_PSEUDO_ADDRESS (255)
#define MB_TCP_PROTOCOL_ID (0) /* 0 = Modbus Protocol */
#ifdef __cplusplus
}
#endif