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Old July 1st, 2011   #2
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Join Date: Aug 2008
Posts: 373

Originally Posted by Martin.nielsen View Post
Why is the number of sub-devices limited to 512 when there is room for 65534?
Is it perhaps to limit the time it takes finding the sub-devices?
Sub-devices were primarily intended for dimmer racks, strip lights, and other devices that have a number of repeating units that need to be configured individually (different Personality, DMX addresses, etc.). If each sub-device takes one DMX slot, 512 is the maximum number that can fit on a universe (since DMX has 512 slots in a Null Start Code packet).

There are hypothetical cases where you might want more than 512, such as a sensor only sub-device. That kind of application is rare, and setting a reasonable upper bound on the number of sub-devices seemed like a reasonable tradeof to account for controllers with limited memory.

Originally Posted by Martin.nielsen View Post
Are there any plans to change this?
Unlikely. Changing this would have significant compatibility implications.

What is your application? There may be another way to solve the problem.

If you need to represent more than 512 sub-devices, your responder could represent itself as a managed proxy that is proxying for an arbitrary number of devices. Or you could make it a multi-port responder. This also has the advantage that it doubles the available bandwidth (which can be important if you need to monitor a large number of sensors with a reasonable update rate).
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