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Old February 7th, 2010   #2
Join Date: Feb 2006
Posts: 429
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Welcome to the forums. There are tighter requirements for the timing in discovery than normal messages due to the fact that the controller is looking for any traffic on the line to indicate the presence of a device in discovery. The reason for Section 3.2.3 is to prevent a branch being missed because one device is holding the line high while another device is trying to respond. By limiting a device from holding a the line in a marking state we are guaranteed that a controller can see the line state change when multiple devices are responding.

Simply put, this additional requirement doesn't exist for non-discovery responses as there should only be one responder active on the line at that point and we don't have to worry about detecting a collision.

For non-discovery messages you'll just need to comply with the timing elements from E1.11 (DMX512) and the other timing requirements in Section 3.2 of E1.20.
Scott M. Blair
RDM Protocol Forums Admin
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