Detect full 48 bits of last data frame in a D-Star transmission #135
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While testing new support for DV Fast Data, I ran across a particular image that reliably generated a bit sequence that the MDMVM firmware interpreted as an end-of-transmission. I dug a bit and discovered that MMDVM only matches on 32 bits of the last data frame instead of the full 48 bits. See http://www.arrl.org/files/file/D-STAR.pdf section 2.1.2, item (6) for details.
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While testing new support for DV Fast Data in g4klx/MMDVMHost#667, I ran across a particular image that reliably generated a bit sequence that the MDMVM firmware interpreted as an end-of-transmission. I dug a bit and discovered that MMDVM only matches on 32 bits of the last data frame instead of the full 48 bits.
(I referenced http://www.arrl.org/files/file/D-STAR.pdf section 2.1.2, item (6))
I tested this patch on my ZUMSpot, a on Raspberry Pi with a ZUM Radio MMDVM-Pi rev 1.0 board (using the MMDVM version of this PR at g4klx/MMDVM#306), and the test image no longer generated an early EOT on either system.
A second commit 08a6c21 is the follow-up work that @g4klx did in https://github.com/g4klx/MMDVM, which I've included in this PR.