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Re: Fwd: DSP-2232/P3T question

At 07:23 PM 2000-11-14 -0500, Charles E. Heisler wrote:
>     Does any one know if P3T.exe needs the sync vector?  As you can see
>below this message from Bob, N4HY is part of a discussion on the
>DSP-2232 reflector regarding the 400 bps modem in the 2232 and it's
>compatibility with Stacey Mills P3T.
>         Thanks,
>             Charlie
>>The DSP2232 decodes the entire data frame but ONLY the
>>data frame.  The sync vector is NOT transmitted.
>>If P3T.exe needs the sync vector, it will not work.
>>I might be able to add the transmission of the
>>sync vector if this is required.
>>Bob, N4HY

No, it does NOT need the sync vector.  I tried to reply to this via the 
dsp2232 reflector, but for some reason, it doesn't recognize me for sending 
any more, though I still receive.

At any rate, what the DSP-2232 is missing are the two CRCC's at the end of 
the 512 byte data block.  Thus, the blocks are actually 514 bytes long, and 
the DSP-2232 grabs only the first 512.  Therefore, there is no way to tell 
if the block is corrupted.  This was a problem in the past with the DSP-12, 
but Bent Bagger updated the code.  An update for the DSP-2232 would be nice 
as well.

P3T.exe will work with the DSP-2232 in the current mode but the modem type 
must be set to "512" instead of "514"... and all of the blocks will be 
marked as "failed" in their logging.

  Stacey E. Mills, W4SM    WWW:    http://www.cstone.net/~w4sm/ham1.html
   Charlottesville, VA     PGP key: http://www.cstone.net/~w4sm/key

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