#10 SysSockPingAsync
SysSockPing is a synchronous function - if you call it in your code it will block that task until the ping timeout expires. There is an alternative SysSockPingAsync, but the code snippet (below) is a little longer. Really one should also call syssockasyncfb.RemoveAllJobs() on application shutdown, but they will timeout anyway themselves.
PROGRAM PLC_PRG VAR syssockasyncfb : SysSocketAsync.SysSockAsyncFB; instAsyncJobParam : SysSocketAsync.ASYNCJOB_PARAM; taskname : STRING := 'Taskname'; taskhandle : SysSocketAsync.RTS_IEC_HANDLE := SysSocketAsync.SysTypes.RTS_INVALID_HANDLE; paramis: SysSocketAsync.tSysSockPing; state: UDINT; //SysSocketAsync.CmpAsyncMgr.GVL result: SysSocketAsync.RTS_IEC_RESULT; replyTime: UDINT; out: SysSocketAsync.RTS_IEC_RESULT; PING: BOOL; handle: SysSocketAsync.RTS_IEC_HANDLE; resultSetJobParam: SysSocketAsync.RTS_IEC_RESULT; END_VAR //general parameters for the async manager instAsyncJobParam.TaskParam.pszTaskname := ADR(taskname); //you could probably put a useful name here instAsyncJobParam.TaskParam.ulTaskPriority := 128; //very low runtime priority instAsyncJobParam.TaskParam.ulTaskSleepTime := 0; //"not used, set to 0" instAsyncJobParam.TaskParam.phTaskHandle := ADR(taskhandle); instAsyncJobParam.TaskParam.ulEndTaskAfterJob := 1; //why not? // parameters for the ping itself paramis.pszIpAddress := '192.168.56.122'; paramis.ulTimeout := 1000; //ms paramis.pulReplyTime := ADR(replyTime); //when the job is finished, the reply time will be stored here paramis.pulOut := ADR(out); //when the job is finished, the result will be stored here //just call the SysSockPingAsync once, and it starts the job. You know it is finished, when PLC_PRG.state = 2 IF PING THEN PING := FALSE; resultSetJobParam := syssockasyncfb.AsyncSetJobParams(ulAsyncJobType:= SysSocketAsync.CmpAsyncMgr.GVL.ASYNCJOB_TASK, ulTimeout:= paramis.ulTimeout * 2, pAsyncJobParams:= ADR(instAsyncJobParam)); handle := syssockasyncfb.SysSockPingAsync(pParam:= ADR(paramis), pudState:= ADR(state), pResult:= ADR(result)); END_IF
Hi i-campbell, Thanks for your sharing. I want to use socket to send and recv messages. Can you give me a example about it using SysSockPingAsync lib?
hi oooo. I only use SysSocket for the ancillary functions, not for actual sockets. If your sockets are UDP/TCP then best to use Net Base Services Library, which has examples at https://forge.codesys.com/prj/codesys-example/
such as https://forge.codesys.com/prj/codesys-example/nbs/home/Home/
OK, Thank you i-campbell.