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RDM General Implementation Discussion General Discussion and questions relating to implementing RDM in a product. |
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#1 | |
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Join Date: Sep 2006
Posts: 26
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The spec states that...
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Cheers, Shaun |
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#2 |
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Shaun,
If I recall correctly the Message Length max is 255. That field points to the Slot # of Checksum High. So I believe the max packet is 257 bytes. If each of those bytes was 255, then the Checksum would be 65535. So in that case it wouldn't roll over. It would be best for everyone to implement it as a modulo anyway as there will be less problems when/if there is any expansion to it in the future.
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#3 |
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Join Date: Sep 2006
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The 257 byte maximum includes the two bytes of the checksum, which clearly aren't covered by the checksum. The checksum only covers 255 bytes.
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#4 |
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Join Date: Jul 2006
Posts: 4
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Just because you can't get to the roll over point doesn't mean you can't say it's modulo. By it's very definition of being a 16-bit number it has to be modulo 0x10000
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Thread | Thread Starter | Forum | Replies | Last Post |
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