Register issuse Please Help! Q series

[MikeyE]

Why do all of my D registers go to zero after a power cycle on the Q plc? I have a bunch of settings (pid values, timer values, ect.) and when I cycle power or download they all get changed to zero or some other number. I changed all the registers and then uploaded all, then I made some changes to the program and downloaded program + parameters and the values changed again,. What am I doing wrong here? HELP! Thanks

[napster]

Use File registers "R" instead of Data registers "D". Edited March 11, 2014 by napster

[panic mode]

which software? did you set latch ranges?

[Crossbow]

You need to specify in PLC parameters the ranges you want backed up by the battery. That's it. Just set a starting and ending address for any memory area.

[MikeyE]

Like this? It doesn't seem to work. I'm not sure what I am missing!

[Veganic]

connect the battery?

[Crossbow]

Did you download those parameters once you changed them?

[kaare_t]

Did you select to download "Device Memory" when executing Write To PLC (see picture)?? In case you did that, remove this setting (you should only transfer the Program + Parameter)... Edited March 12, 2014 by kaare_t

[MikeyE]

Thanks for all your help, I was downloading device memory which was changing all the registers to when I had saved them. Unfortunately all of my settings were not what I wanted them to be when I saved the device memory. The registers make it through a power cycle and retain their value. I appreciate all of your responses, sorry I didn't reply sooner as I am out in the field!

[kaare_t]

No problem. Good luck in the field...

[Cmos]

Hi I had the same problem with D registers going to zero on power cycle, and have added the latch ranges in the device properties. After doing this, and a rebuild all, I get 2 errors, both the same: "The Range of for VAR of word devices overlaps the with the range of for VAR_RETAIN by device/label automatic setting" I am using labels in my project and have been allowing GX work2 to automatically assign them. I am trying to latch 12000 to 12280 Any idea what's wrong? Thanks

[Crossbow]

Tools, Device-Variable Auto Assign Settings (or something along those lines. GX Works2 still has to convert labels back to PLC addresses, and basically by setting the retentive ranges, you restricted which addresses it can use. The error says you have some addresses in both the VAR and VAR_RETAIN pools. Address ranges overlap. There is information on this topic in the GX Works2 manual.

[Cmos]

Hi Do you know if there is a way to turn off the auto assignment of addresses, so that the existing addresses assigned remain as they are? I have installed the program and tested and debugged, and the registers I want to have ratained are mostly user inputs from the HMI. It seems like a big oversight if you cant use labels and have their data retentative. If I turn off the automatic asdignment in <Tool/Device labal automatic assign setting> I get an error naming the first label that appears alphebetically in the global label list. Error : " The number of word device (VAR range) points for Device/Label Automatic Assign-Setting fall short (Bin_LF_Max)" Thanks for your help!

[Veganic]

Cmos, I encountered this problem - being unable to make automatically assigned variables retentive. The only solution I could find was to assign fixed addresses for those that needed to be retentive.

[Cmos]

Ok thanks Veganic I will do it through the ladder. I was hoping there would be something I was missing. Thanks for the heads up

[Crossbow]

Use VAR_RETAIN type variables for the ones to be battery backed. Then when the compiler allocates the addresses to them, they will be assigned from the battery backed range. Once you set a range as battery backed in the parameters, the auto assign screen has settings for ranges from which to auto-allocate from both normal and backed areas. I will attempt to make some screen shots later on.