Problem with SFC 15. Correct value for RECORD parameter.

Hi,

I have problem with SFC 15. I tried to anderstand why, but I don't have a concept.
Please help me.

My HW Config :

CPU
|
| Profibus DP
|
|
|-------ET200M(AO 8 channels)

8 Analog Channels = 8 x 2 bytes= 16 bytes

I call

CALL  "DPWR_DAT"
LADDR  :=W#16#100
RECORD :=P#M 40.0 BYTE 16
RET_VAL:=MW30

and I have RET_VAL=80B1

If I use

RECORD :=P#M 40.0 BYTE 2

or

RECORD :=P#M 40.0 BYTE 4

I have RET_VAL=0   (It works)

Why SFC15 don't work with RECORD :=P#M 40.0 BYTE 16 ?

Jan Kowalski

Hello Jan;

Your code seems correct for your call of SFC 15; the error code returned is that the source area does not match the destination area (not the same size). See the attached screencapture, from the   System and Standard Functions manual:

System Software for S7-300/400 System and Standard Functions Volume 1 and Volume 2

I find that error very strange, since your code points to MB 40 to MB55, which in any case should be available at any moment (even if the values inside might not be initialized correctly at the moment you call the function).

If I may suggest a workaround: create a DB in your program with 8 words area, initialize the 8 words to the values you want to send to the AO on your ET 200M, and try using this as a source for your test. If you use DB10, the source address would be P# DB10.DBX0.0 Byte 16.

I would be interested in knowing the results of this test. If it works, then we could look at why the M area is causing a problem.

Hope this helps,

Daniel Chartier

I know what meants 80b1 but I don't understand why I have it.

I created 2 DBs:

DB1
DATA : ARRAY  [1 .. 16 ] OF BYTE ;

and

DB2
DATA : ARRAY  [1 .. 8 ] OF WORD ;

then I tried to use:

1.

RECORD :=P#db1.dbx0.0 byte 16  

RET_VAL=80b1

2.
RECORD :=P#db1.dbx0.0 word 8   

RET_VAL=80b1

3.

RECORD :=P#DB2.DBX 0.0 WORD 8  

RET_VAL=80b1

4.
RECORD :=P#DB2.DBX 0.0 byte 16  

RET_VAL=80b1

Jan Kowalski

 hi,

LGL

If I use

RECORD :=P#M 40.0 BYTE 2

or

RECORD :=P#M 40.0 BYTE 4

I have RET_VAL=0   (It works)

Does it work with P#M40.0 BYTE 8?

in the block-diagram I can see two DAC. I guess the consistency is limited to each DAC

maybe someone can confirm this,

hope this helps,

regards,

I tried

P#M 40.0 BYTE 8

still

80b1