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Old March 2nd, 2010   #12
berntd
Senior Member
 
Join Date: Jan 2008
Posts: 102
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Quote:
Originally Posted by sblair View Post
I just Queue the PID itself. Then when the controller asks I just send whatever the current value is for that PID.

In a limited device, you could use a single BIT to denote the PID. Thus with a single BYTE you could support queueing for up to 8 messages!
Also true but how would that work for the same PID across 12/24 subdevices?

Example: The operating mode of the device is changed. This can change:
1: The preheat value
2: The DMX personality,
3: The output limit
Of each subdevice / channel.

That results in a total of up to 24*3 + 1 = 73 queued messages and lots of them with with the same PID.

So to make that work, I suppose it will need some sort of processing engine that will just manage the message queue and it will need to sort out sub-devices as well as pids and strictly speaking also the values.
It also needs to keep track of how many messages remain as well as the LAST_MESSAGE. :D

If the operating mode is changed a few times in successtion, buffer full and lost messages / no way for controller to see the changes will result right?

It makes the Enttech Controllers "Refresh" And "Get" / "Set" buttons look very
atractive.

Regards
Bernt
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