For All You RSView Experts

I'm assuming the answer is "no," but what the hey, I'll ask anyway...

RSView ME with Control Logix PLC. Can I access any array dimension from RSView by using an internal variable in the HMI to offset? For example:

Array in PLC: MyArray[30]

RSView: {[MyPLC]MyArray[ArrayOffset]}

where: ArrayOffset is the internal variable in the PanelView.

Thanks.

lendyck said:

I'm assuming the answer is "no," but what the hey, I'll ask anyway...

RSView ME with Control Logix PLC. Can I access any array dimension from RSView by using an internal variable in the HMI to offset? For example:

Array in PLC: MyArray[30]

RSView: {[MyPLC]MyArray[ArrayOffset]}

where: ArrayOffset is the internal variable in the PanelView.

Thanks.

Click to expand...

Can't see why not. I just created a Memory Tag of type Analog called offset and used it in an expression to access an array of REALs within the Clgx. The compilier accepted the syntax as valid. Only thing I have not been able to do is test live with a PLC

RSView doesn't really care too much about what's inside the {}. It seems to me that it takes the address literally, and does not know enough to use the internal tag's value, instead of the name.

I was trying to push some work onto the PV, since it doesn't really do anything anyway, but I think the work will have to be done in the PLC.

One workaround would be to have the PV write the array value to a temporary memory location in the PLC, as well as send the PLC the array offset, then let the PLC deal with it.

On another note, RSView has a lot of glitchy things. Such as when referencing tags on an offline Clgx project, if any changes are made in the Clgx program, RSView does not interpret the tags correctly...everything seems to be offset. The only way I know how to get it to see the tags properly is to shutdown the apps, and kill all the Rockwell services, and then restart everything. What a pain.

Is there a solution to this question: to accesses the ControlLogix arrays via an internal ArrayOffset?

Example:
{[PLC]MyArray[ArrayOffset]} instead of using constants {[PLC]MyArray[0..n]}

You can make a tag in the tag database of the RSView project, and select memory rather than device, then use that tag for your pointer/offset/index value

You shouldn't need to offload "logic" to the PV though, the contrologix has lots of horsepower

We have been unsucessful in accesing anything from RSViewME if we try this indirect method. it appears that the accessed address cannot be changed at runtime.

bernie_carlton said:

We have been unsucessful in accesing anything from RSViewME if we try this indirect method. it appears that the accessed address cannot be changed at runtime.

Click to expand...

This is exactly what I am seeing. The internal memory Offset does not seem to change the devices index at runtime. NOTE: we are using RSViewME

bernie_carlton said:

We have been unsucessful in accesing anything from RSViewME if we try this indirect method. it appears that the accessed address cannot be changed at runtime.

Click to expand...

I wonder if this was done intentionally to avoid potential runtime errors if the index is out of range.

Or, in RSView32 it may have been done inentionally as an attempt to keep people from cheating the tag licensing scheme. And maybe that got carried over into RSView ME/SE.

Indexed addressing from the HMI would certainly be extremely useful and powerful, and I haven't used any systems that support it.

This is defintely not indirect/variable addressing but it is a way to sort of accomplish this, provided it's not too big of an array.

Couldn't get my pic to show up correctly. This is from the Expression Editor.

If Variable == 0 Then {[CLX_Data]Setpoint[0]} Else
If Variable == 1 Then {[CLX_Data]Setpoint[1]} Else
If Variable == 2 Then {[CLX_Data]Setpoint[2]} Else
If Variable == 3 Then {[CLX_Data]Setpoint[3]} Else
If Variable == 4 Then {[CLX_Data]Setpoint[4]} Else
If Variable == 5 Then {[CLX_Data]Setpoint[5]} Else {[CLX_Data]Setpoint[6]}



OG