Dear guys, the FIFO is a pain for me. I am using siemens s7 to program it. When I use FC84 ATT table to store the data, it can work properly. But when I try to read the data by using FC85 FIFO, every time I call the fuction there is one data automaticlly stored inside the ATT table and the number of entries remain unchanged. Where is the data from??? The data supposed to be stored only when I call FC84, RIGHT? I attached the file, can anyone pls help me to find where am I WRONG?
BTW, you must use "Pulse" to triger the FC 85 and FC 84, the normal contact can not work.
Thank you in advance.
BTW, you must use "Pulse" to triger the FC 85 and FC 84, the normal contact can not work.
Thank you in advance.