实验5485总线及Modbus通讯协议实验.docx

1、实验5485总线及Modbus通讯协议实验课程名称：嵌入式软件技术开课机房：11号机房 2012年4月24日星期二8：1011:35 专业班级通信09(2 )班 学号Xb07680215姓名夏陆豪实验项目名称实验5485总线及Modbus通讯协议实验指导教师陈玮一、实验任务与实验目的 实验目的1. 了解Modbus协议及其应用2. 了解freeModbus库及其移植方法3. 掌握Modbus协议中常用命令的应用实验任务1. 将开源Modbus协议库freeModbus移植到EASY ARM8962开发板上二、报告内容 Freemodbus是modbus协议在嵌入式处理器上的实现。包括AVR,P

2、IC,WIN32等等平台。它是开放性源代码，可用于商业目的。它实现了Modbus RTU/ASCII、TCP三种传输方式，当前版本是1.5，支持以下功能： 读输入寄存器 (0x04) 读保持寄存器 (0x03) 写单个寄存器 (0x06) 写多个寄存器 (0x10) 读/写多个寄存器 (0x17) 读取线圈状态 (0x01) 写单个线圈 (0x05) 写多个线圈 (0x0F) 读输入状态 (0x02) 报告从机标识 (0x11)本实现基于最新的标准并且与标准完全兼容。接收和传输Modbus RTU/ASCII数据帧是通过一个由硬件提取层的调用来驱动状态机实现的。这就使得协议非常容易移植到其他的

3、平台之上。当接收一个完整的数据帧后，该数据帧被传入Modbus应用层，数据帧的内容在该层内得到解析。为方便地增加新的Modbus功能，Freemodbus在应用层提供了钩子函数Hooks。如果用到了Modbus TCP协议，那么当准备处理一个新数据帧的时候，移植层就必须首先向协议层发送一个事件标志。然后，协议栈调用一个返回值为接收到的Modbus TCP数据帧的函数，并且开始处理这个数据帧。如果数据有效，则响应的Modbus反馈帧将提供给移植层生成反馈帧。最后，该反馈帧被发送到客户端。二、实现FreeModbus协议所需要的软/硬件需求Modbus协议对硬件的需求非常少基本上任何具有串行接口，

4、并且有一些能够容纳modbus数据帧的RAM的微控制器都足够了。 一个异步串行接口，能够支持接收缓冲区满和发送缓存区空中断。 一个能够产生RTU传输所需要的t3.5 字符超时定时器的时钟。对于软件部分，仅仅需要一个简单的事件队列。 The STR71X/FreeRTOS 移植使用 FreeRTOS 队列作为事件队列来减少 Modbus 任务所需要的时间。小点的微控制器往往不允许使用操作系统，在那种情况下，可以使用一个全局变量来实现该事件队列(The Atmel AVR 移植使用这种方式实现)。实际的存储器需求决定于所使用的 Modbus 模块的多少。下表列出了所支持的功能编译后所需要的存储器。

5、 ARM 项数值是使用 GNUARM 编译器 3.4.4 使用 -O1 选项得到的。 AVR项数值是使用 WinAVR 编译器 3.4.5 使用 -Os 选项编译得到的。ModuleARM CodeARM RAM (static)AVR CodeAVR RAM (static)Modbus RTU (Required)1132Byte272Byte1456Byte266ByteModbus ASCII (Optional)1612Byte28Byte1222Byte16ByteModbus Functions 11180Byte34Byte1602Byte34ByteModbus Core (

6、Required)924Byte180Byte608Byte75BytePorting Layer (Required 2)1756Byte16Byte704Byte7ByteTotals7304Byte530Byte5592Byte398Byte1:实际大小决定于可支持的Modbus功能码的多少。 功能码可以在头文件mbconfig.h中进行配置。2:决定于硬件。已完成的移植：Cortex M3 devices: Atmel AT91SAM3S.ARM devices: STR71X with FreeRTOS/GCC. See STR71X/simple2.c for an example

7、. STR71TCP with FreeRTOS/lwIP/GCC. This port includes FreeRTOS, lwIP and a fully working PPP stack. The lwIP, PPP and FreeRTOS part is generic and therefore can be used for other ports ( or other projects ). LPC214X with Keil. See LPC214X/demo.c for an example. This port uses the Keil ARM Compiler 2

8、.41. AT91SAM7X with FreeRTOS/Rowley. See AT91SAM7X_ROWLEY/demo.c for an example.AVR devices: ATMega8/16/32/128/168/169 with WinAVR. See AVR/demo.c for an example.Coldfire devices: MCF5235 with GCC. See MCF5235/demo.c for an example. MCF5235 with CodeWarrior and FreeRTOS port for ColdFire. See MCF523

9、5CW/demo.c for an example. MCF5235/TCP with GCC. This port features FreeRTOS and the lwIP stack. The lwIP part is generic and therefore it should be used as a basis for other lwIP ports.MSP430 devices MSP430F169 with Rowley Crossworks. See MSP430/demo.c for an example. MSP430F169 with GCC. See MSP43

10、0/demo.c for an example.Z8Encore devices Z8F6422 and Z8F1622 port. See Z8ENCORE/demo.c for an example. The port uses ZDS II - Z8 Encore! 4.10.1 as development environment.Win32: A Win32 Modbus RTU/ASCII Port. A Win32 Modbus/TCP Port.Linux: A Linux (uCLinux or other distributions) Modbus RTU/ASCII Po

11、rt.任务一PortTimer.c中：xMBPortTimersInit( USHORT usTim1Timerout50us ) 负责配置一个时基，vMBPortTimersEnable( ) 启用这个时基。比如执行:xMBPortTimersInit( 10000 );vMBPortTimersEnable( );Port.c/* - System includes -*/#include hw_types.h#include interrupt.h /zd/* - Modbus includes -*/* - Variables -*/int VIC_Temp;/* - Start im

12、plementation -*/void EnterCriticalSection() IntMasterDisable(); /* Disable Interruptions _zd */void ExitCriticalSection() IntMasterEnable(); /* Enable Interruptions _zd */PortSerial.c/* * FreeModbus Libary: LM3S Port * Copyright (C) 2007 Tiago Prado Lone * * This library is free software; you can re

13、distribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * This library is distributed in the hope that it will be useful, * but WITHOUT ANY

14、WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this library; if not, write to the Free Softwa

15、re * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA * * File: $Id: portserial.c,v 1.1 2007/04/24 23:15:18 wolti Exp $ */#include hw_memmap.h#include hw_ints.h #include hw_types.h#include sysctl.h#include hw_uart.h#include gpio.h#include interrupt.h#include uart.h/*-*/#inclu

16、de port.h/* - Modbus includes -*/#include mb.h#include mbport.h/* - Start implementation -*/void vMBPortSerialEnable(BOOL xRxEnable, BOOL xTxEnable) if (TRUE = xRxEnable) UARTIntEnable(UART0_BASE, UART_INT_RX | UART_INT_RT); else UARTIntDisable(UART0_BASE, UART_INT_RX | UART_INT_RT); if (TRUE = xTxE

17、nable) UARTIntEnable(UART0_BASE, UART_INT_TX); else UARTIntDisable(UART0_BASE, UART_INT_TX); void vMBPortClose(void) UARTIntDisable(UART0_BASE, UART_INT_RX | UART_INT_RT | UART_INT_TX); IntEnable (INT_UART0);BOOL xMBPortSerialInit(UCHAR ucPORT, ULONG ulBaudRate, UCHAR ucDataBits, eMBParity eParity)

18、/* UCHAR PORT; ULONG BaudRate; UCHAR DataBits; eMBParity Parity; PORT = ucPORT; BaudRate = ulBaudRate; DataBits = ucDataBits; Parity = eParity; */ SysCtlPeripheralEnable (SYSCTL_PERIPH_UART0); SysCtlPeripheralEnable (SYSCTL_PERIPH_GPIOA); GPIOPinTypeUART(GPIO_PORTA_BASE, GPIO_PIN_0 | GPIO_PIN_1); /

19、Configure the UART for ulBaudRate, 8-EVEN-1 operation. UARTConfigSetExpClk(UART0_BASE, SysCtlClockGet(), ulBaudRate, (UART_CONFIG_WLEN_8 | UART_CONFIG_STOP_ONE | UART_CONFIG_PAR_EVEN); / Enable the UART interrupt. IntEnable (INT_UART0); UARTIntEnable(UART0_BASE, UART_INT_RX | UART_INT_RT | UART_INT_

20、TX); return TRUE;BOOL xMBPortSerialPutByte(CHAR ucByte) UARTCharPutNonBlocking(UART0_BASE, ucByte); return TRUE;BOOL xMBPortSerialGetByte(CHAR * pucByte) *pucByte = UARTCharGetNonBlocking(UART0_BASE); return TRUE;/* * Create an interrupt handler for the transmit buffer empty interrupt * (or an equiv

21、alent) for your target processor. This function should then * call pxMBFrameCBTransmitterEmpty( ) which tells the protocol stack that * a new character can be sent. The protocol stack will then call * xMBPortSerialPutByte( ) to send the character. */static void prvvUARTTxReadyISR(void) pxMBFrameCBTr

22、ansmitterEmpty();/* * Create an interrupt handler for the receive interrupt for your target * processor. This function should then call pxMBFrameCBByteReceived( ). The * protocol stack will then call xMBPortSerialGetByte( ) to retrieve the * character. */static void prvvUARTRxISR(void) pxMBFrameCBBy

23、teReceived();/ UART INT HANDLER ZDvoid UART0IntHandler(void) unsigned long ulStatus; ulStatus = UARTIntStatus(UART0_BASE, true); UARTIntClear(UART0_BASE, ulStatus); if (ulStatus & (UART_INT_RT | UART_INT_RX) prvvUARTRxISR(); if (ulStatus & UART_INT_TX) prvvUARTTxReadyISR(); /* * FreeModbus Libary: L

24、M3S Port * Copyright (C) 2007 Tiago Prado Lone * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later ver

25、sion. * * This library is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the G

26、NU Lesser General Public * License along with this library; if not, write to the Free Software * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA * * File: $Id: porttimer.c,v 1.1 2007/04/24 23:15:18 wolti Exp $ */PortTimer.c#include hw_memmap.h#include hw_ints.h#include hw_ty

27、pes.h#include sysctl.h#include interrupt.h#include hw_timer.h#include hw_types.h#include gpio.h#include timer.h/* - Platform includes -*/#include port.h/* - Modbus includes -*/#include mb.h#include mbport.h/* - Start implementation -*/BOOL xMBPortTimersInit(USHORT usTim1Timerout50us) SysCtlPeriphera

28、lEnable (SYSCTL_PERIPH_TIMER0); GPIOPinTypeTimer(TIMER0_BASE, TIMER_A); TimerConfigure(TIMER0_BASE, TIMER_CFG_32_BIT_PER); TimerLoadSet(TIMER0_BASE, TIMER_A, (SysCtlClockGet() / 20000) * usTim1Timerout50us); TimerIntEnable(TIMER0_BASE, TIMER_TIMA_TIMEOUT); TimerEnable(TIMER0_BASE, TIMER_A); IntEnable (INT_TIMER0A); return TRUE;void vMBPortTimersEnable() TimerEnable(TIMER0_BASE, TIMER_A);void vMBPortTimersDisable() TimerDisable(TIMER0_BASE, TIMER_A);void TIMERExpiredISR(void) (void