I think I have go 'back to basics' with what I've been doing/learnt with XNET and CAN. Sorry to ask this but my understanding of how things work was very wrong. I currently have certain Cyclic Frames being output ok using Frame Out Queued mode. This starts the Frames being output continuously as per timings stated in database. I create a default Payload for each Frame using Signal's default values as also defined in my database. If I then want to update a Signal value in one of these Frames I create a Signal Out Single-point session. After a 'XNET Write (Signal Single-point)' this creates another Frame being output on top of the already running Frame output, which I didn't want. I just want to update values in a Frame already being output continuously under timing control of XNET. So, instead....if I want to have Frames (Cyclic) to be sent continuously, e.g. I have 10 Frames each with multiple signals to start transmitting with the default values in my database, and then have a VI that allows a specific Signal to be changed to a new value I would have to first create a 'Signal Out Single-point' session and pass it EVERY signal in my database, and then keep a track of all the Values (for all Signals), which are then passed each time I call 'XNET Write (Signal-point).vi' ? Much appreciate any advice. I have searched and there are a coupe of previous posts stating the same dilema/confusion but am not clear still of how to do this.

@AndyJD wrote: So, instead....if I want to have Frames (Cyclic) to be sent continuously, e.g. I have 10 Frames each with multiple signals to start transmitting with the default values in my database, and then have a VI that allows a specific Signal to be changed to a new value I would have to first create a 'Signal Out Single-point' session and pass it EVERY signal in my database, and then keep a track of all the Values (for all Signals), which are then passed each time I call 'XNET Write (Signal-point).vi' ? That's how I would do it. The Single Point Output is useful for things that just need to be sent out periodically, but doesn't have any Request/Response communication. Attached is an example that might be helpful. You need to add the Interface, and update the constant of Signals with the ones you actually use. But after that just run it, and it will write them. Then from the UI you select the signal you want, change the value, then click Update and it will update that signal's value.

Automotive and Embedded Networks

Cyclic CAN Frame output and then updating signals

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Thanks to you both.

So the hardware based counter and CRC calculation scripts will not work with Frame Output Queued mode then?

I need to provide the ability to ramp signal values up and down (at the same time as a hardware message tick and CRC)...or any sequence of signal values that go out on a per Frame transmit