Mitsubishi MELSEC-L series Programming Manual page 263

[ST]
IF((LDP(TRUE,Var_Flag_Inst)=TRUE) AND (Var_Flag_Exe=FALSE))THEN
MOVP(TRUE,H1,Var_ControlData[2]);
(* Sets open error code of connection number 1 *)
MOVP(TRUE,H0,Var_ControlData[3]);
(* Sets latest error information *)
SET(TRUE,Var_Flag_Exe);
END_IF;
IF(Var_Flag_Exe=TRUE)THEN
ZP_ERRRD(TRUE,"U0",Var_ControlData,Var_Result);
END_IF;
IF(Var_Result[0]=TRUE)THEN
IF(Var_Result[1]=FALSE)THEN(* Normal completion *)
MOVP(TRUE,Var_ControlData[4],Var_ErrorInfo);
END_IF;
IF(Var_Result[1]=TRUE)THEN (* Error completion *)
MOVP(TRUE,Var_ControlData[1],Var_ErrorCode);
END_IF;
RST(TRUE,Var_Flag_Exe);
END_IF;
5.4 CC-Link IE Controller Network, MELSECNET/H, and Ethernet Instruction
(* Turns execution flag ON*)
(* Reads error information *)
(* Execution finished *)
(* Stores error information*)
(* Stores error code *)
(* Turns execution flag OFF *)
5.4.21 ERRRD instruction
ZP_ERRRD
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