建立了个原始数据叫“NewTag”
R_ID是4 然后选BSEND/BRCV

建了个动作1秒执行一次：
#include "apdefap.h"

int gscAction( void )
{
BYTE a[4];
#pragma option(mbcs)
// WINCC:TAGNAME_SECTION_START
// syntax: #define TagNameInAction "DMTagName"
// next TagID : 1
// WINCC:TAGNAME_SECTION_END

// WINCC:PICNAME_SECTION_START
// syntax: #define PicNameInAction "PictureName"
// next PicID : 1
// WINCC:PICNAME_SECTION_END
GetTagRaw("NewTag",a,4); //Return-Type: BOOL
SetTagByte("b1",a[1]); //Return-Type: BOOL
SetTagByte("b2",a[2]); //Return-Type: BOOL
SetTagByte("b3",a[3]); //Return-Type: BOOL
SetTagByte("b4",a[4]); //Return-Type: BOOL


return 0;
}


S7300里加上通讯块：

A M 0.0
= L 28.0
BLD 103
A M 0.1
= L 28.1
BLD 103
CALL FB 12 , DB12
REQ :=L28.0
R :=L28.1
ID :=W#16#1
R_ID :=DW#16#4
DONE :=M0.2
ERROR :=M0.3
STATUS:=MW2
SD_1 :=DB1.DBD0
LEN :=MW10 // 长度4
NOP 0

发送不成功？？高手指导