在eTS调用C++方法的过程中，需要使用到Node_API、Cmake等工具来做中间转换。
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DevEco创建项目和模块
创建项目只要是API9就行。
基于OpenHarmony 系统通过S7协议读取西门子PLC数据-开源基础软件社区
创建一个S7模块要用到这个C++模板。
基于OpenHarmony 系统通过S7协议读取西门子PLC数据-开源基础软件社区
应用架构。整个应用架构可以分为三部分：C++侧、eTS侧、工具链。
C侧：包含各种文件的引用、C或者C代码、Node_API将C++函数与JavaScript关联的信息等。eTS侧：包含界面UI、自身方法，调用引用包的方法等。工具链：包含Cmake打包工具在内的系列工具。在eTS调用C++方法的过程中，需要使用到Node_API、Cmake等工具来做中间转换，整个架构及其关联关系如下：调用、打包流程。
基于OpenHarmony 系统通过S7协议读取西门子PLC数据-开源基础软件社区
在eTS调用C++方法的过程中，调用、打包流程如下：
基于OpenHarmony 系统通过S7协议读取西门子PLC数据-开源基础软件社区
移植SNAP7到OpenHarmony
SNAP7移植框架文件在此开源仓库的cpp文件夹里面。
库文件：
基于OpenHarmony 系统通过S7协议读取西门子PLC数据-开源基础软件社区
cpp文件：
基于OpenHarmony 系统通过S7协议读取西门子PLC数据-开源基础软件社区
把上面文件加入编译，加入hilog。
基于OpenHarmony 系统通过S7协议读取西门子PLC数据-开源基础软件社区
把测试代码执行起来
在add中加入s7_main函数。
基于OpenHarmony 系统通过S7协议读取西门子PLC数据-开源基础软件社区
修改IP地址，机架号，插槽号，和DB块读取的地址。
基于OpenHarmony 系统通过S7协议读取西门子PLC数据-开源基础软件社区
在module.json5中添加网络权限。
基于OpenHarmony 系统通过S7协议读取西门子PLC数据-开源基础软件社区
运行调试
基于OpenHarmony 系统通过S7协议读取西门子PLC数据-开源基础软件社区
基于OpenHarmony 系统通过S7协议读取西门子PLC数据-开源基础软件社区
#include #include #include "snap7/snap7.h"#include "snap7/client.h"#include "hilog/log.h"#ifdef OS_WINDOWS# define WIN32_LEAN_AND_MEAN# include #endif TS7Client *Client; byte Buffer[65536]; // 64 K buffer int SampleDBNum = 1000; char *Address = "10.168.100.2"; // PLC IP Address int Rack = 0,Slot = 1; // Default Rack and Slot int ok = 0; // Number of test pass int ko = 0; // Number of test failure bool JobDone=false; int JobResult=0;//------------------------------------------------------------------------------// Async completion callback //------------------------------------------------------------------------------// This is a simply text demo, we use callback only to set an internal flag...void S7API CliCompletion(void *usrPtr, int opCode, int opResult){ JobResult=opResult; JobDone = true;}//------------------------------------------------------------------------------// SysSleep (copied from snap_sysutils.cpp) multiplatform millisec sleep//------------------------------------------------------------------------------void SysSleep(longword Delay_ms){#ifdef OS_WINDOWS Sleep(Delay_ms);#else struct timespec ts; ts.tv_sec = (time_t)(Delay_ms / 1000); ts.tv_nsec =(long)((Delay_ms - ts.tv_sec) * 1000000); nanosleep(&ts, (struct timespec *)0);#endif}//------------------------------------------------------------------------------// Usage Syntax//------------------------------------------------------------------------------void Usage(){ printf("Usage\n"); printf(" client [Rack=0 Slot=2]\n"); printf("Example\n"); printf(" client 192.168.1.101 0 2\n"); printf("or\n"); printf(" client 192.168.1.101\n"); getchar();}//------------------------------------------------------------------------------// hexdump, a very nice function, it"s not mine.// I found it on the net somewhere some time ago... thanks to the author ;-)//------------------------------------------------------------------------------#ifndef HEXDUMP_COLS#define HEXDUMP_COLS 16#endifvoid hexdump(void *mem, unsigned int len){ unsigned int i, j; for(i = 0; i < len + ((len % HEXDUMP_COLS) ? (HEXDUMP_COLS - len % HEXDUMP_COLS) : 0); i++) { /* print offset */ if(i % HEXDUMP_COLS == 0) { printf("0x%04x: ", i); } /* print hex data */ if(i < len) { printf("%02x ", 0xFF & ((char*)mem)[i]); } else /* end of block, just aligning for ASCII dump */ { printf(" "); } /* print ASCII dump */ if(i % HEXDUMP_COLS == (HEXDUMP_COLS - 1)) { for(j = i - (HEXDUMP_COLS - 1); j <= i; j++) { if(j >= len) /* end of block, not really printing */ { putchar(" "); } else if(isprint((((char*)mem)[j] & 0x7F))) /* printable char */ { putchar(0xFF & ((char*)mem)[j]); } else /* other char */ { putchar("."); } } putchar("\n"); } }}//------------------------------------------------------------------------------// Check error//------------------------------------------------------------------------------bool Check(int Result, const char * function){ printf("\n"); printf("+-----------------------------------------------------\n"); printf("| %s\n",function); printf("+-----------------------------------------------------\n"); if (Result==0) { printf("| Result : OK\n"); printf("| Execution time : %d ms\n",Client->ExecTime()); printf("+-----------------------------------------------------\n"); ok++; } else { printf("| ERROR !!! \n"); if (Result<0) printf("| Library Error (-1)\n"); else printf("| %s\n",CliErrorText(Result).c_str()); printf("+-----------------------------------------------------\n"); ko++; } return Result==0;}//------------------------------------------------------------------------------// Multi Read//------------------------------------------------------------------------------void MultiRead(){ // Multiread buffers byte MB[16]; // 16 Merker bytes byte EB[16]; // 16 Digital Input bytes byte AB[16]; // 16 Digital Output bytes word TM[8]; // 8 timers word CT[8]; // 8 counters // Prepare struct TS7DataItem Items[5]; // NOTE : *AMOUNT IS NOT SIZE* , it"s the number of items // Merkers Items[0].Area =S7AreaMK; Items[0].WordLen =S7WLByte; Items[0].DBNumber =0; // Don"t need DB Items[0].Start =0; // Starting from 0 Items[0].Amount =16; // 16 Items (bytes) Items[0].pdata =&MB; // Digital Input bytes Items[1].Area =S7AreaPE; Items[1].WordLen =S7WLByte; Items[1].DBNumber =0; // Don"t need DB Items[1].Start =0; // Starting from 0 Items[1].Amount =16; // 16 Items (bytes) Items[1].pdata =&EB; // Digital Output bytes Items[2].Area =S7AreaPA; Items[2].WordLen =S7WLByte; Items[2].DBNumber =0; // Don"t need DB Items[2].Start =0; // Starting from 0 Items[2].Amount =16; // 16 Items (bytes) Items[2].pdata =&AB; // Timers Items[3].Area =S7AreaTM; Items[3].WordLen =S7WLTimer; Items[3].DBNumber =0; // Don"t need DB Items[3].Start =0; // Starting from 0 Items[3].Amount =8; // 8 Timers Items[3].pdata =&TM; // Counters Items[4].Area =S7AreaCT; Items[4].WordLen =S7WLCounter; Items[4].DBNumber =0; // Don"t need DB Items[4].Start =0; // Starting from 0 Items[4].Amount =8; // 8 Counters Items[4].pdata =&CT; int res=Client->ReadMultiVars(&Items[0],5); if (Check(res,"Multiread Vars")) { // Result of Client->ReadMultivars is the "global result" of // the function, it"s OK if something was exchanged. // But we need to check single Var results. // Let shall suppose that we ask for 5 vars, 4 of them are ok but // the 5th is inexistent, we will have 4 results ok and 1 not ok. printf("Dump MB0..MB15 - Var Result : %d\n",Items[0].Result); if (Items[0].Result==0) hexdump(&MB,16); printf("Dump EB0..EB15 - Var Result : %d\n",Items[1].Result); if (Items[1].Result==0) hexdump(&EB,16); printf("Dump AB0..AB15 - Var Result : %d\n",Items[2].Result); if (Items[2].Result==0) hexdump(&AB,16); printf("Dump T0..T7 - Var Result : %d\n",Items[3].Result); if (Items[3].Result==0) hexdump(&TM,16); // 8 Timers -> 16 bytes printf("Dump Z0..Z7 - Var Result : %d\n",Items[4].Result); if (Items[4].Result==0) hexdump(&CT,16); // 8 Counters -> 16 bytes };}//------------------------------------------------------------------------------// List blocks in AG//------------------------------------------------------------------------------void ListBlocks(){ TS7BlocksList List; int res=Client->ListBlocks(&List); if (Check(res,"List Blocks in AG")) { printf(" OBCount : %d\n",List.OBCount); printf(" FBCount : %d\n",List.FBCount); printf(" FCCount : %d\n",List.FCCount); printf(" SFBCount : %d\n",List.SFBCount); printf(" SFCCount : %d\n",List.SFCCount); printf(" DBCount : %d\n",List.DBCount); printf(" SDBCount : %d\n",List.SDBCount); };}//------------------------------------------------------------------------------// CPU Info : catalog//------------------------------------------------------------------------------void OrderCode(){ TS7OrderCode Info; int res=Client->GetOrderCode(&Info); if (Check(res,"Catalog")) { printf(" Order Code : %s\n",Info.Code); printf(" Version : %d.%d.%d\n",Info.V1,Info.V2,Info.V3); };}//------------------------------------------------------------------------------// CPU Info : unit info//------------------------------------------------------------------------------void CpuInfo(){ TS7CpuInfo Info; int res=Client->GetCpuInfo(&Info); if (Check(res,"Unit Info")) { printf(" Module Type Name : %s\n",Info.ModuleTypeName); printf(" Serial Number : %s\n",Info.SerialNumber); printf(" AS Name : %s\n",Info.ASName); printf(" Module Name : %s\n",Info.ModuleName); };}//------------------------------------------------------------------------------// CP Info//------------------------------------------------------------------------------void CpInfo(){ TS7CpInfo Info; int res=Client->GetCpInfo(&Info); if (Check(res,"Communication processor Info")) { printf(" Max PDU Length : %d bytes\n",Info.MaxPduLengt); printf(" Max Connections : %d \n",Info.MaxConnections); printf(" Max MPI Rate : %d bps\n",Info.MaxMpiRate); printf(" Max Bus Rate : %d bps\n",Info.MaxBusRate); };}//------------------------------------------------------------------------------// PLC Status//------------------------------------------------------------------------------void UnitStatus(){ int res=0; int Status=Client->PlcStatus(); if (Check(res,"CPU Status")) { switch (Status) { case S7CpuStatusRun : printf(" RUN\n"); break; case S7CpuStatusStop: printf(" STOP\n"); break; default : printf(" UNKNOWN\n"); break; } };}//------------------------------------------------------------------------------// Upload DB0 (surely exists in AG)//------------------------------------------------------------------------------void UploadDB0(){ int Size = sizeof(Buffer); // Size is IN/OUT par // In input it tells the client the size available // In output it tells us how many bytes were uploaded. int res=Client->Upload(Block_SDB, 0, &Buffer, &Size); if (Check(res,"Block Upload (SDB 0)")) { printf("Dump (%d bytes) :\n",Size); hexdump(&Buffer,Size); }}//------------------------------------------------------------------------------// Async Upload DB0 (using callback as completion trigger)//------------------------------------------------------------------------------void AsCBUploadDB0(){ int Size = sizeof(Buffer); // Size is IN/OUT par // In input it tells the client the size available // In output it tells us how many bytes were uploaded. JobDone=false; int res=Client->AsUpload(Block_SDB, 0, &Buffer, &Size); if (res==0) { while (!JobDone) { SysSleep(100); } res=JobResult; } if (Check(res,"Async (callback) Block Upload (SDB 0)")) { printf("Dump (%d bytes) :\n",Size); hexdump(&Buffer,Size); }}//------------------------------------------------------------------------------// Async Upload DB0 (using event wait as completion trigger)//------------------------------------------------------------------------------void AsEWUploadDB0(){ int Size = sizeof(Buffer); // Size is IN/OUT par // In input it tells the client the size available // In output it tells us how many bytes were uploaded. JobDone=false; int res=Client->AsUpload(Block_SDB, 0, &Buffer, &Size); if (res==0) { res=Client->WaitAsCompletion(3000); } if (Check(res,"Async (Wait event) Block Upload (SDB 0)")) { printf("Dump (%d bytes) :\n",Size); hexdump(&Buffer,Size); }}//------------------------------------------------------------------------------// Async Upload DB0 (using polling as completion trigger)//------------------------------------------------------------------------------void AsPOUploadDB0(){ int Size = sizeof(Buffer); // Size is IN/OUT par // In input it tells the client the size available // In output it tells us how many bytes were uploaded. JobDone=false; int res=Client->AsUpload(Block_SDB, 0, &Buffer, &Size); if (res==0) { while (!Client->CheckAsCompletion(&res)) { SysSleep(100); }; } if (Check(res,"Async (polling) Block Upload (SDB 0)")) { printf("Dump (%d bytes) :\n",Size); hexdump(&Buffer,Size); }}//------------------------------------------------------------------------------// Read a sample SZL Block//------------------------------------------------------------------------------void ReadSzl_0011_0000(){ PS7SZL SZL = PS7SZL(&Buffer); // use our buffer casted as TS7SZL int Size = sizeof(Buffer); // Block ID 0x0011 IDX 0x0000 normally exists in every CPU int res=Client->ReadSZL(0x0011, 0x0000, SZL, &Size); if (Check(res,"Read SZL - ID : 0x0011, IDX 0x0000")) { printf(" LENTHDR : %d\n",SZL->Header.LENTHDR); printf(" N_DR : %d\n",SZL->Header.N_DR); printf("Dump (%d bytes) :\n",Size); hexdump(&Buffer,Size); }}//------------------------------------------------------------------------------// Unit Connection//------------------------------------------------------------------------------bool CliConnect(){ Client->SetConnectionType(3); int res = Client->ConnectTo(Address,Rack,Slot); if (Check(res,"UNIT Connection")) { printf(" Connected to : %s (Rack=%d, Slot=%d)\n",Address,Rack,Slot); printf(" PDU Requested : %d bytes\n",Client->PDURequested()); printf(" PDU Negotiated : %d bytes\n",Client->PDULength()); }; return res==0;}//------------------------------------------------------------------------------// Unit Disconnection//------------------------------------------------------------------------------void CliDisconnect(){ Client->Disconnect();}//------------------------------------------------------------------------------// Perform readonly tests, no cpu status modification//------------------------------------------------------------------------------void PerformTests(){ OrderCode(); CpuInfo(); CpInfo(); UnitStatus(); ReadSzl_0011_0000(); UploadDB0(); AsCBUploadDB0(); AsEWUploadDB0(); AsPOUploadDB0(); MultiRead();}//------------------------------------------------------------------------------// Tests Summary//------------------------------------------------------------------------------void Summary(){ printf("\n"); printf("+-----------------------------------------------------\n"); printf("| Test Summary \n"); printf("+-----------------------------------------------------\n"); printf("| Performed : %d\n",(ok+ko)); printf("| Passed : %d\n",ok); printf("| Failed : %d\n",ko); printf("+----------------------------------------[press a key]\n"); getchar();}float GetPLCData(){ float value0 = 0; byte value1[4]= {0}; Client->DBRead(1,1244,4,value1); *((byte*)&value0 + 0) = value1[3]; *((byte*)&value0 + 1) = value1[2]; *((byte*)&value0 + 2) = value1[1]; *((byte*)&value0 + 3) = value1[0]; return value0;}//------------------------------------------------------------------------------// Main //------------------------------------------------------------------------------float s7_main(){ float result = 0; Client = new TS7Client(); Client->SetConnectionType(3); Client->ConnectTo("192.168.1.2", 0, 1); //PLC的IP地址，机架号，插槽号 OH_LOG_Print(LOG_APP, LOG_INFO, 0xFF00, "PluginManager", "[S7 CONNECT]Connected"); if(Client->Connected() == true){ OH_LOG_Print(LOG_APP, LOG_INFO, 0xFF00, "PluginManager", "[S7 CONNECT]连接成功"); } float value0 = 0; byte value1[4]= {0}; Client->DBRead(1,1111,4,value1); *((byte*)&value0 + 0) = value1[3]; *((byte*)&value0 + 1) = value1[2]; *((byte*)&value0 + 2) = value1[1]; *((byte*)&value0 + 3) = value1[0]; result = value0; delete Client; return result;} 想了解更多关于开源的内容，请访问：
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