Siemens SINUMERIK 840Di Function Manual page 1401

2. Read word of position offset 8 without semaphore and store in MW 104:
CALL FC 21 (
Function
5: Update control signals to channel:
The purpose of function 5 is to transmit important control signals at high speed in between
cyclic data transfers. Data bytes 6 and 7 of user interfaces DB21 to DB30 are transferred to
the NC. The channel is specified in parameter "IVAR1". This enable, for example, the feed
disable, read-in disable to be transferred outside of the PLC cycle.
The following signals are relevant:
Signal
Enable
Funct
S7Var
IVAR1
Error
ErrCode
6: Update control signals to axes:
The purpose of function 6 is to transmit important control signals at high speed in between
cyclic data transfers. Data byte 2 of application interface DB31 to DB61 is transferred to the
NC. The transfer is performed for all activated axes. This allows the servo enable to be
transferred outside the PLC cycle, for example.
The following signals are relevant:
Signal
Enable
Funct
S7Var
IVAR1
Error
ErrCode
PLC Basic Program Solution Line (P3 sl)
Function Manual, 08/2005 Edition, 6FC5397-0BP10-0BA0
Enable := M 10.0,
Funct := B#16#3,
S7Var := P#M 104.0 WORD 1,
IVAR1 := 8,
IVAR2 := -1,
Error := M 10.1,
ErrCode := MW12);
Type Type
I Bool
I Byte
I Any
I Int
Q Bool
Q Int
Type Type
I Bool
I Byte
I Any
I Int
Q Bool
Q Int
// if True, FC 21 is active
//Read data
Value range Remarks
1= FC 21 active
5 5: Control signals to channel
S7 data storage area Not used
1. Max. channel Channel number
1: "Funct" invalid
10: Channel no. invalid
Value range Remarks
1= FC 21 active
6 6: Control signals to axes
S7 data storage area Not used
0
1: "Funct" invalid
Detailed Description
2.12 Block descriptions
2-207