It depends on the size and type of data. The incoming data has the number of BOOL, that is, the switching value, and only two binary numbers, 0 and 1. It only occupies one bit of the address, and the representation method is V0.0M0.0I0.0 and so on. VB is a byte data address, that is, an 8-bit binary number less than 255 or an integer greater than-126. For example: 5; -8; 12; -45; 124; 254 and so on. Data in the range of 255 can use this VB. VW is a word data address, which is a 16-bit binary number less than 65535 or an integer greater than -32767. For example: 3422; - 10000; 453, wait. VD is a double-word data address or a floating-point data address, which is a floating-point number, such as: 23.445; 35.546; Storage address 4567. 124546, etc. It is also an integer less than 4294967295, and the storage address is greater than-2/-2 147483648；; It is also a pointer address storage area. You can send data such as VW5 to VD0.