s7 300 to simoreg

If I want to send 6 words (PPO4) from PLC (CPU 314 C– 2DP) to the drive (SIMOREG) over profibus with SFC15 (1st word for control word), then does the 1st word have bit to bit direct correspondence to the control word?



As for example, whether bit 0 of the 1st word corresponds to bit0 of control word of drive, bit1 to bit1 of control word of drive and so on or it corresponds reversely.



Please help.



Shyamal

They do not correspond bit for bit, the bytes are swapped.

Dear LD,

Thank you very much for your immediate response.

For a specific case, if I have the word 0100 1001 1101 1011 in PLC and send it to the control word through SFC15, will the control word look:



Bit15 = 0, Bit14 = 1, Bit13 = 0, Bit12 = 0, Bit11 = 1, Bit10 = 0, Bit9 = 0, Bit8 = 1,
Bit7 = 1, Bit6 = 1, Bit5 = 0, Bit4 = 1, Bit3 = 1, Bit2 = 0, Bit1=1, Bit0 = 1

Where is the word in the plc - are you referring two DBB locations in a data block ?

Say, from a function block I am calling SFC15 with the following code:

CALL "DPWR_DAT"

LADDR :=#Drive_Address_HEX

RECORD :=P#DIX 16.0 BYTE 12

RET_VAL:=#Ret_Val_Error2



And say, the word DIW16 has been referred with the data mentioned in my second post to the control word of the drive.

DIX bits map to the drive control word as follows:

DIX16.0 = Drive Control word bit 8
DIX16.1 = Drive Control word bit 9
DIX16.2 = Drive Control word bit 10
DIX16.3 = Drive Control word bit 11
DIX16.4 = Drive Control word bit 12
DIX16.5 = Drive Control word bit 13
DIX16.6 = Drive Control word bit 14
DIX16.7 = Drive Control word bit 15

DIX17.0 = Drive Control word bit 0
DIX17.1 = Drive Control word bit 1
DIX17.2 = Drive Control word bit 2
DIX17.3 = Drive Control word bit 3
DIX17.4 = Drive Control word bit 4
DIX17.5 = Drive Control word bit 5
DIX17.6 = Drive Control word bit 6
DIX17.7 = Drive Control word bit 7

Thank you LD, thank you so much. You are really great.

Shyamal

Thanks LD

I have one more question if second PZD word is spindle feedback then how it is? Is it floating point format or other ? How to convert it to real?

If the drive is configured to send back one word representing the spindle speed, then it will be a signed integer where 16384=100% speed.
To convert to real use:

L iSpeed
ITD
DTR
T rSpeed

Thanks LD