Siemens Simatic S7 Series

Libraries
9.2 USS library instructions
S7-200 SMART
System Manual, 09/2015, A5E03822230-AC
425
9.2.2.5
USS_WPM_x instruction
Table 9- 14 USS_WPM_x instructions
LAD / FBD
STL
Description
CALL USS_WPM_W, XMT_REQ, EEPROM,
Drive, Param, Index, Value,
DB_Ptr, Done, Error
CALL USS_WPM_D, XMT_REQ, EEPROM,
Drive, Param, Index, Value,
DB_Ptr, Done, Error
CALL USS_WPM_R, XMT_REQ, EEPROM,
Drive, Param, Index, Value,
DB_Ptr, Done, Error
There are three write instructions for the USS protocol:
• USS_WPM_W instruction writes an unsigned word
parameter.
• USS_WPM_D instruction writes an unsigned dou-
ble word parameter.
• USS_WPM_R instruction writes a floating-point
parameter.
Only one read (USS_RPM_x) or write (USS_WPM_x)
instruction can be active at a time.
The USS_WPM_x transactions complete when the drive acknowledges receipt of the
command or when an error condition is posted. The logic scan continues to execute while
this process awaits a response.
Table 9- 15 Valid operands for the USS_WPM_x instructions
Inputs/outputs
Data type
Operands
XMT_REQ
BOOL
I, Q, M, S,SM,T,C,V,L, Power Flow conditioned by a rising edge detection element
EEPROM
BOOL
I, Q, M, S, SM, T, C, V, L, Power Flow
Drive
BYTE
VB, IB, QB, MB, SB, SMB, LB, AC, *VD, *AC, *LD, Constant
Param, Index
WORD
VW, IW, QW, MW, SW, SMW, LW, T, C, AC, AIW, *VD, *AC, *LD, Constant
DB_Ptr
DWORD
&VB
Value WORD
DWORD, REAL
VW, IW, QW, MW, SW, SMW, LW, T, C, AC, AQW, *VD, *AC, *LD
VD, ID, QD, MD, SD, SMD, LD, *VD, *AC, *LD
Done
BOOL
I, Q, M, S, SM, T, C, V, L
Error
BYTE
VB, IB, QB, MB, SB, SMB, LB, AC. *VD, *AC, *LD