RSLogix help for a DirectSoft user

I have a fair amount of experience with DirectSoft and ADC PLCs. I need to be able to analyze a SLC5/05 program give a RSLogix print out. Nothing too fancy, but I am being slowed down by lack of familiarity with the AB.

Can some suggest a primer for reading an AB ladder?

A couple a 'quick questions' for some one familiar with both systems.

If the print out I have, in MOV and SCP boxes there seems to be two numbers for each paramater. First there is either a number or an address, then there is a second number followed by a "<". What's the second number for?

How does a MOV work in AB? Is it like a LD box followed by an OUT box in ADC (Load Source, Output to Dest)?

Are the following true?:

-----(L)--| = ----(SET)
-----(U)--| = ----(RST)

O:X/Y = channel Y of discrete output module in slot X
I:X/Y = channel Y of discrete input module in slot X

O:X.Y = value of channel Y of analog output module in slot X
I:X.Y = value of channel Y of analog input module in slot X

hanziou said:

Can some suggest a primer for reading an AB ladder?

Click to expand...

A 'must have' for your task is the Instruction Set Reference Manual, available HERE...

It will answer all of your questions and more...

While digging up the reference manual, I came across THIS manual which should also be helpful to you... :nodi:



-Eric

Mov is just like you think
The L and U are retentitve, so they don't go low when the power is cycled.

SCP is a scaled linearization of the 2 values, with a high and low value.

O:X/Y = Bit Level can look at a discrete value in slot x

O:X.Y = Word Level can look at Analog Values in Slot X Channel Y

Now to your questions...

If the print out I have, in MOV and SCP boxes there seems to be two numbers for each paramater. First there is either a number or an address, then there is a second number followed by a "<". What's the second number for?

That's the 'actual' or 'current' value of that location. In you case, it's the last value read from the processor before going offline. This would be equivalent to looking at the V-memory editor values in DirectSOFT.

Remember that all values are retentive through a power cycle in the SLC. In the Koyo stuff, you pick which are/are not retentive.

How does a MOV work in AB? Is it like a LD box followed by an OUT box in ADC (Load Source, Output to Dest)?

Yes, that's basically it.

Are the following true?:

-----(L)--| = ----(SET)
-----(U)--| = ----(RST)

Yes.

O:X/Y = channel Y of discrete output module in slot X
I:X/Y = channel Y of discrete input module in slot X

O:X.Y = value of channel Y of analog output module in slot X
I:X.Y = value of channel Y of analog input module in slot X

Refer to that second manual I posted for a better explanation than I could give...



-Eric

I see Marc has snuck in with some good info...



-Eric

Thank You. Thank you.

Those manuals look like just what I needed.
Thanks for the explanation of the <.

Amazing how much easier these things are to read when I know the symbols mean.
-Hans

SET = Latch? ... RESET = Unlatch? ... close - but not quite ...

Greetings hanziou,

Eric Nelson said:

Remember that all values are retentive through a power cycle in the SLC. In the Koyo stuff, you pick which are/are not retentive.

Click to expand...

he's absolutely correct ... and if you want to dig deeper into this particular subject, then this thread contains more about it than you probably wanted to know ...

tip: there could possibly be some safety considerations involved in just simply transferring "SET/RESET" constructions from AD into identical "LATCH/UNLATCH" constructions for AB ...

Eric Nelson said:

Remember that all values are retentive through a power cycle in the SLC. In the Koyo stuff, you pick which are/are not retentive.

Click to expand...

Unless the SLC's CPU battery dies because you left it turned off all week.