How to initialize a module only on reboot and resume of program ?

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Hello Alex,

I had to do something similar when initializing drives on servo motors. I’ll assume you’re using an IRC5 controller, but I believe the same approach applies to OmniCore controllers.

First, your program is supposed to resume exactly where it stopped, unless you make a change in the code. The program pointer (PP) is lost whenever you modify your RAPID code. In my application, the PP always stays in the same place unless I explicitly send it back to Main or change my code.

For your module initialization, there are several approaches. You could create an event routine that runs your initialization at controller startup. Personally, I preferred using internal I/O signals that aren’t tied to any physical device.

• I have a DO signal, initially set to 0, called jawReadyOut, and a DI signal called jawReadyIn.
• They’re cross-connected, with jawReadyIn as the result and jawReadyOut as Actor1.
• When I need my servo motors, I use TestDI to check the condition. If it’s not met, I run my initialization routine.
• At the end of initialization, I SetDO jawReadyOut, 1, which also sets jawReadyIn to 1 thanks to the cross-connection.
  
  

As soon as the controller restarts, jawReadyOut returns to its initial value, so the initialization procedure will be called on the next use.

I used to use a VAR bool, but that only resets when you return to Main().

There’s probably a more intuitive way to do this, but in our case it works really well!

Does this help?

Hello Charle, thank you for your help

When you say you do a TestDI, how do you go about it? I think I understand, but I want to be sure we’re talking about the same thing.

I have an initialization procedure for my drives that I call in Main and every time I need to use my servo motors:

PROC jawOpen()

jawStart;

[rest of jawOpen]

ENDPROC

PROC jawStart()

IF TestDI jawReadyIn = FALSE THEN

[drive initialization];

SetDO jawReadyOut, 1;

ENDIF

ENDPROC.

So whenever I call jawOpen() or jawClose(), jawStart() checks jawReadyIn, runs initialization if it’s false, sets jawReadyOut so that on the next check TestDI jawReadyIn returns true and the module won’t initialize again. It may not be the most intuitive approach, but this temporary solution has proven reliable for us

Ah, okay, that makes sense to me. I’ll give it a try. Thanks for your help!