DPRD_DAT, DPWR_DAT what are the restrictions?

Ive had troubles in the past reading data using the SFC14 and writing with SFC15.

For example tried reading and writing to a watson marlow pump wich had this setup (Se attached image)..

I read 12byte to a 12byte long structure and write from a 6byte long structure.

I never got this to work so i had to use direct access instead..

So I wonder if there is any more restrictions than that the are to read/write must be 3bytes or larger than 4 bytes long?

Interesting, what were the error codes on sfc calls? And what did the call look like?

I will get my hands on a pump later this year (dont know exactly when..) and I will try again..

The last time we had a hurry and I didnt note the error codes.. But this time around I will have some more time at my hands.. So then I can post the error codes..

I will post the code use last time later this week and the new code that will be used this time for interfacing the pump to..

I made some cleaning up in the code in the spare time..