How do I access individual Bits of a DINT?

hmmm, I have seen some huge programs in the controllogix line, and none have used bit packing. I would bet that the programmer was a little more worried about the extra programming time as opposed to the “extra PLC space”. unless your plc program is ginormous I would be surprised if it is really an issue. :slight_smile:

We use bit packing into DINTs for our first out and horn logic. One program has 3000 bits packed into DINTs. DINT packing is still used in the CLX line, especially if you are using remote comms via some legacy network protocol

yeah, I do use bit packing for first out logic, but I just havent seen much of it for comms anymore, should have been more specific. used to be we used it alot in the offshore environment due to limited communications options. thats not really an issue anymore.

Ok, good things come to those who wait. Accessing bits in a DINT. SINT, INT and LINT will be possible in the 7.1 release.

The current development release has support for accessing bits in a DINT. SINT, INT. Because RSLogix doesn’t include bits in LINT data types, I left out LINT.

Woo Hoo!

Thanks… I promise I’l be patient this time :thumb_left:
(LINT types aren’t a problem for us as the PLC programmers here prefer DINT’s for just about everything)

Could you please post an example of the tag syntax for accessing a bit within a DINT in a Controllogix? We are using ver. 7.2.6 and can’t seem to access individual bits. Tag example: [SS_Cfax]Global.MOTORS.MOTORS[1].HOA
Also, even if we could, it doesn’t appear (assumption here) that the individual bits would be available when configuring Client or Gateway Event scripts. Is this true?
Thanks

Let me clarify the previous muddled question - Can Ignition access individual bits in a DINT without creating a new tag for each bit?
Ex: SS_CFAX/MOTORS/MOTOR_1/HOA.0
When adding the .0 or /0 to the end of the tag an error occurs. Is this possible some other way?
Thanks

[quote=“scott_stc”]Let me clarify the previous muddled question - Can Ignition access individual bits in a DINT without creating a new tag for each bit?
Ex: SS_CFAX/MOTORS/MOTOR_1/HOA.0
When adding the .0 or /0 to the end of the tag an error occurs. Is this possible some other way?
Thanks[/quote]

A new SQLTag is required for each bit.

Reading through this thread and gradually understanding what is being said. I have a SLC and can write to the PLC with [OfficeSlc]B3:2.0 or [OfficeSlc]B3:2/0 with a toggle button. I try the one-shot button and the bit gets turned on and stays “Writing…” and never turns off. So maybe I don’t understand the one shot. How does one pulse a bit?

Figured out the “one-shot” is actually a latched. The user manual spoke of a “momentary button” but that does not come up when I drag a tag to the screen. Got the one-shot to work, but would like to know if there is a momentary button?

Picture’s worth 1000 words. Dragging a tag onto a screen is not the only way to create a component, just a shortcut for some common actions.

2 posts were split to a new topic: Accessing individual bits in controllogix