XTinyModbus

A small embedded Modbus protocol stack, written in C language, support master and slave, support discrete mapping, support non-blocking and blocking read and write mode, and provide a complete example, can be transplanted to different processors, simple to use, portable.

0.Log

2022/10/7
Add a set of APIs to allow mixed non-blocking and blocking mode calls in host mode in bare metal state.
Check out the functions related to xx_MixXXX in MDM_RTU_Fun.c.
Fix the bug of time frame calculation error.

2020/11/23
Optimization of slave protocol parsing strategy, more stable
Optimize the loop queue to make it more adaptable
The loop queue memory is modified to the user specified
Host added RTOS support, can be opened through MD_RTU_USED_OS under md_rtu_config. h, the default is closed, has been transplanted to XTinyRTOS, can be modified by md_rtu_sysinteraction. c transplant
Other modifications and optimizations

2020/9/24
Added the function of not polling when the slave is disconnected, the master can use the MDM_RTU_CB_SetDisPollEnFlag function to set it,
You can use the MDM_RTU_CB_ClrDisFlag function to reset.
Add a simple host sending controller.
Fix the BUG of mixed call of host blocking mode and non-blocking mode.
All comments in the code are modified to English.

2020/9/6 Add a multi slave example.
Add some macro for testing.

2020/8/31 Add MD_ RTU_ Configure the protocol stack with config. H.
Test macro configuration added.
Modification of file name.
Some other changes.

2020/6/6 Fixed a size end error.
Slaver corrected errors in reading discrete mapping functions.
Slave supports broadcast addresses.
Master host adds send cache.

2020/4/28 Discrete mappings for Master hosts will have to specify slave Numbers instead of sharing.

2020/4/23 Slave Fixes a BUG in the CRC macro.
Fixed discrete mapping table master and slave size inconsistency BUG.
Master Fixes bugs that cause errors in read commands and dependent variables.

The serial port initialization location is changed to md_rtu_serial.c and mdm_rtu_serial.c.
Fixed some naming conventions.

2020/4/13 Slave adds the send cache, which is optional and enabled by default through the macro configuration in md_rtu_fun. h.

2020/4/12 Added transceiver conversion control.

2020/4/10 Code to add comments, specification of comments, optimize the structure of the file storage.

2020/4/4 Slave fixes a bug with a minimal probability that the timer overflow can cause packet loss.

2020/4/3 Salve changes the discrete mapping, and the input is mapped separately

2020/3/31 Salve adds host write callback function listen.
Salve adds partial exception and error code support.
Salve fixed an error sending unspaced frames.
Optimize CRC16 efficiency.

1.Features

ModBus RTU salve feature:

1. realize Modbus RTU salve
   
2. join the double-queue mechanism.
   
3. implement function code 1,2,3,4,5,6,15,16.
   
4. support discrete mapping between modbus address and local address.
   
5. provide user to read and write modbus address interface.
   
6. support multiple slaves.
   

ModBus RTU master feature:

1. realize Modbus RTU master
   
2. support non-blocking type read and write
   
3. support blocking type read and write
   
4. support regular retransmission
   
5. support timeout retransmission
   
6. support read data discrete mapping
   

2.How to transplant

The example gives an example of a port in the STM32F1 series of chips that need to be ported to other chips, need to modify md_rtu_serial.c, implement port port port function migration, and need to call serial port and timer functions in the interrupt function. < br > Serial port transplantation function:

/*Send function*/
void MDSSerialSendBytes(uint8 *bytes,uint16 num){
	/*The BSP sending function is called below*/
	uart_send_bytes(bytes,num);
}

Call the following function in the timer interrupt function, the timer interval is 100US:

/*This function is called in the timer*/
void MDSTimeHandler100US(uint32 times){
	if(_pModbus_RTU==NULL){return;}
	_pModbus_RTU->mdRTUTimeHandlerFunction(_pModbus_RTU ,times);
}

The following function is called in the serial port receive interrupt

/*The BSP layer interrupts the receiving call to this function*/
void MDSSerialRecvByte(uint8 byte){
	if(_pModbus_RTU==NULL){return;}
	_pModbus_RTU->mdsRTURecByteFunction(_pModbus_RTU , byte);
}

3.How to use

You can see an example of using the md_rtu_app.c file. The following code adds two address mapping items, and the modbus address corresponds to the local address:

uint16 regCoilData0[32]={1,2,3,4,5,6,7,8,9,10,11,12};
RegCoilItem regCoilItem0={
. ModbusAddr =0x0000, /* address in MODBUS */
. ModbusData =regCoilData0, /* mapped memory unit */
. ModbusDataSize =32, /* the size of the map */
.addrtype =REG_TYPE /* the type of the map */
};
uint16 regCoilData1[4]={0};
RegCoilItem regCoilItem1={
. ModbusAddr =0x0000, /* address in MODBUS */
. ModbusData =regCoilData1, /* mapped memory unit */
. ModbusDataSize =64, /* the size of the map */
.addrtype =BIT_TYPE /* type of mapping */
};
	/*Add an address map*/
	if(RegCoilListAdd(&modbusS_RTU, &regCoilItem0)==FALSE){
		return FALSE;
	}
	if(RegCoilListAdd(&modbusS_RTU, &regCoilItem1)==FALSE){
		return FALSE;
	}

The following code can be used to read and write modbus registers and coil values:

Uint16 temp = 0 XFF;
Uint16 temp1 [] = {1, 2, 3, 4, 5};
MDS_RTU_WriteBits (& modbusS_RTU, 1, 5, & temp);
MDS_RTU_WriteReg (& modbusS_RTU, 11, temp);
MDS_RTU_WriteRegs (& modbusS_RTU, 5, 5, temp1, 0).

4.Future features

Modbus RTU host, Modbus ASCII host and slave.

XTinyModbus

一个应用于嵌入式方面的小型Modbus协议栈，采用C语言编写，支持master与slave，支持离散映射，支持非阻塞与阻塞读写模式，并提供完整示例，可以移植到不同的处理器，使用简单，移植方便。

0.日志

2020/11/23
优化从机协议解析策略，更加稳定
优化循环队列，使得其适应性更强
循环队列内存修改为用户指定
主机增加RTOS支持，可以通过MD_RTU_Config.h下的MD_RTU_USED_OS开启，默认关闭，已经移植好XTinyRTOS，可以通过修改MD_RTU_Sysinterface.c进行移植
其它修改及优化

2020/9/24
增加从机掉线不轮询功能，主机可以使用MDM_RTU_CB_SetDisPollEnFlag函数进行设置，
可以使用MDM_RTU_CB_ClrDisFlag函数进行复位。
增加简单的主机发送控制器。
修复主机阻塞模式和非阻塞模式混合调用的BUG。
代码中所有注释修改为英文。

2020/9/6 增加多从机示例。
增加一些测试用的宏。

2020/8/31 增加MD_RTU_Config.h进行协议栈配置。
增加测试配置宏。
文件命名的修改。
一些其它的修改。

2020/6/6 修正一个大小端错误。
Slaver 修正离散映射函数读取的错误。
从机支持广播地址。
Master 主机添加发送缓存。

2020/4/28 Master 主机的离散映射将必须指定从机号，不在采用共用方式。

2020/4/23 Slave 修复CRC宏的一个BUG。
修复离散映射表主从机大小不一致的BUG。
Master 修复读命令，因变量从用导致错误的BUG。
串口初始化位置修改到MD_RTU_Serial.c 与 MDM_RTU_Serial.c内。
修正一些命名规范。

2020/4/13 Slave增加发送缓存，该项为可选项，可以通过MD_RTU_Fun.h内的宏配置，默认开启。

2020/4/12 增加收发转换控制。

2020/4/10 代码添加注释，规范注释方式，优化文件存放结构。

2020/4/4 Slave修复定时器溢出可能导致丢包的极小概率bug。

2020/4/3 Slave更改离散映射方式，输入分开映射

2020/3/31 Slave添加主机写回调函数监听。
Slave添加部分异常码与错误码支持。
Slave修复发送未进行帧间隔的错误。
优化CRC16效率。

1.特性

ModBus RTU Slave 特性：
1)实现Modbus RTU Slave
2)加入双队列机制。
3)实现功能码1,2,3,4,5,6,15,16。
4)支持modbus地址与本机地址离散映射。
5)提供用户读写modbus地址接口。
6)支持多个从机。

ModBus RTU master 特性：
1)实现Modbus RTU master
2)支持非阻塞式读写
3)支持阻塞式读写
4)支持定时重发
5)支持超时重传
6)支持读数据离散映射

2.如何移植

示例中给出了在STM32F1系列芯片的一个移植示例，去过需要移植到其它芯片，需要对MD_RTU_Serial.c进行修改，实现串口函数的移植，以及需要在中断函数中调用串口与定时器的 函数。
串口移植函数：

/*发送函数*/
void MDSSerialSendBytes(uint8 *bytes,uint16 num){
	/*在下面调用bsp的发送函数*/
	uart_send_bytes(bytes,num);
}

在定时器中断函数中调用下面这个函数，定时器间隔100US：

/*定时器中调用该函数*/
void MDSTimeHandler100US(uint32 times){
	if(_pModbus_RTU==NULL){return;}
	_pModbus_RTU->mdRTUTimeHandlerFunction(_pModbus_RTU ,times);
}

在串口接收中断中调用下面这个函数

/*bsp层中断接收调用这个函数*/
void MDSSerialRecvByte(uint8 byte){
	if(_pModbus_RTU==NULL){return;}
	_pModbus_RTU->mdsRTURecByteFunction(_pModbus_RTU , byte);
}

3.如何使用

使用方式可以查看MD_RTU_APP.c文件的使用示例。 下面代码添加两个地址映射项，吧modbus地址与本地地址对应起来：

uint16 regCoilData0[32]={1,2,3,4,5,6,7,8,9,10,11,12};
RegCoilItem regCoilItem0={
	.modbusAddr=0x0000,				/*MODBUS中的地址*/
	.modbusData=regCoilData0,	/*映射的内存单元*/
	.modbusDataSize=32,				/*映射的大小*/
	.addrType=REG_TYPE				/*映射的类型*/
};
uint16 regCoilData1[4]={0};
RegCoilItem regCoilItem1={
	.modbusAddr=0x0000,				/*MODBUS中的地址*/
	.modbusData=regCoilData1,	/*映射的内存单元*/
	.modbusDataSize=64,				/*映射的大小*/
	.addrType=BIT_TYPE				/*映射的类型*/
};
	/*添加一个地址映射*/
	if(RegCoilListAdd(&modbusS_RTU, &regCoilItem0)==FALSE){
		return FALSE;
	}
	if(RegCoilListAdd(&modbusS_RTU, &regCoilItem1)==FALSE){
		return FALSE;
	}

下面的代码可以实现用户端读写modbus 寄存器与线圈值：

	uint16 temp=0xff;
	uint16 temp1[]={1,2,3,4,5};
	MDS_RTU_WriteBits(&modbusS_RTU,1,5,&temp);
	MDS_RTU_WriteReg(&modbusS_RTU,11, temp);
	MDS_RTU_WriteRegs(&modbusS_RTU,5,5, temp1,0);

4.未来功能 Modbus ASCII主机与从机。

5.谢鸣 紫§尘、依叶知秋