B1

Data type. Possible values are 0: VW, 1: IW, or 2: QW

B2

Initial address

B3

Type of variable. Possible values are 0: WORD, 2: DWORD, 3: DWORD2, 4: REAL, 5: REAL2, 10: INT, 12: DINT, or 13: DINT2. Please check topic Types of Variables for more information

B4

Not used, leave it in 0 (zero)