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Corner case for encoding delta value
Fred Malabre / CME Group <>
8 Jun 2010 10:07AM ET Hello,
Let's say I have a field defined as U64 to encode with delta value.
The reference value is 0. I want to send the value 12178 (then as a signed value because of delta encoding).
The corresponding binary value is 0000 ... 0000 0010 1111 1001 0010.
Encoding with FAST, I would end up with:
(0)101 1111 (1)001 0010
=> Continuation byte is in parenthesis in the example above.
=> Only 2 bytes are sent according to the rule truncating most significant bits set to zero.
Now, for the receiving side, when you get this value (which end up being 5F92 in hexa), it looks like some decoders are using the first bit as the sign bit (which would be bit #13 in my example, the one just after the stop bit 0).
What am I missing here? Is the encoding described above expected?
Thanks,
Fred.
Corner case for encoding delta value
Fred Malabre / CME Group 8 Jun 2010 10:07AM ET
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