micrologix1000 shift register

Hello everybody:
I need to control the shift register's length from HMI, I'm using the plc micrologix 1000 and this plc doesn't permit to use a variable at length adress. Could somebody give me the way to do it
tanks

I have never tried this but the picture below should work. The control data file holds the length value. I am assuming the shift instruction you are using. If its not the "BSL" then tell us what instruction you are using.

EDIT: Yes there should be a condition in front of the "BSL" instruction ( I'm lazy).

Thanks a lot!

I will try today and
after that i will tell you if it works.