Difference in advancedHMIcontrols and mfgControlAdvancesHMIcontrols ?

[mikehell]

Can I assume that the MFG controls are ASYNC while the others are not?   In other words a  BeginWrite fires off an ASYNC call, a "fire and forget" ?  I will need to send some commands in a rapid fire machine-gun fashion (via an asp.net page written in vb.net).  I haven't put in the AHMI stuff yet,  but even doing something simple like changing a label (in an update panel) this fast causes a backup and misses cues. 

[Archie]

What are you calling the "MFG controls" and the "others"?

When it comes to speed of writing to a PLC, the synchronous vs. asynchronous are going to be very close in response, within microseconds of each other. The bottle neck is how fast the PLC can accept the values and respond. It varies widely by PLC. The fastest I have seen is less than 2ms for an L8x series ControlLogix and as slow as 15ms on some Modbus devices.

[mikehell]

What are you calling the "MFG controls" and the "others"?

When it comes to speed of writing to a PLC, the synchronous vs. asynchronous are going to be very close in response, within microseconds of each other. The bottle neck is how fast the PLC can accept the values and respond. It varies widely by PLC. The fastest I have seen is less than 2ms for an L8x series ControlLogix and as slow as 15ms on some Modbus devices.

I have 2 sets of DLLS. One set is called mfgControl.AdvancedHMI.Controls and mfgControl.AdvancedHMI.Drivers and another set that appear to be the same thing, except without the mfgControl part in the name.

My Async issue isn't an issue with being able to write to the device fast enough. The issue is that when the event is fired off it takes a bit of time for control to be released back from the function, in that amount of time it's been blocked, another event gets fired off (async javascript) and it gets missed.   I have "cues" going along a moving timeline that need to be fired off as they are hit on the timeline, if that makes sense.  What's the difference in beginWrite and Write?

Thanks for your help

[Archie]

The DLLs are the libraries that make up all of the controls and components. One set is an extension of the other.

BeginWrite puts the request into a queue and returns immediately back to a the caller.
Write puts it in the queue, then waits for a response from the PLC before returning to the caller.