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FreeEMS Serial Protocol 
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malcom2073 wrote:
As per a document I'm assuming Fred already sent you (If he did not, ask and I'll see if I can find it again)

Yes, this is the first thing I did, and asked him not to share on the forum as they're out of date and should not become a defacto standard. This is one of the things he meant by secrecy above.

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Now that you have the packet read, you should de-escape the bytes. Once again that is documented in the protocol document which bytes mean what. Once all that wonderful magic is finished, you now have a complete datalog packet.

I sincerely hope that you do NOT do it like this!!!! Reading guts out of the packet before deescaping and checksumming is completely flawed! The packet must be received, deescaped, and checksummed IN THAT ORDER. ONLY then can the header be read and the contents interpreted appropriately.

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The datalog packet format <SNIP> but be advised, this is subject to change as the datalog format will in the future be configurable.
Quote:
The datalog packet format <SNIP> but be advised, this is subject to change as the datalog format has been configurable for more than two years.

Fixed! I've used it several times over that period when I've needed specific data at a higher frequency. You just have to change your external tooling to suit. Laborious, but only a little.

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Thu Jul 31, 2014 1:09 am
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LQFP112 - Up with the play

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Fred wrote:
I sincerely hope that you do NOT do it like this!!!! Reading guts out of the packet before deescaping and checksumming is completely flawed! The packet must be received, deescaped, and checksummed IN THAT ORDER. ONLY then can the header be read and the contents interpreted appropriately.


Of course, I misspoke. You don't touch the header bytes until after you escape the whole thing and verify the checksum.

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Thu Jul 31, 2014 1:27 am
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n00bs, do NOT PM or email tech questions! Use the forum!
The ever growing list of FreeEMS success stories!


Thu Jul 31, 2014 1:30 am
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DIP8 - Involved

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Thank you so much malcom2073.

Wilbert


Thu Jul 31, 2014 11:09 pm
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LQFP112 - Up with the play
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Fred wrote:
malcom2073 wrote:
As per a document I'm assuming Fred already sent you (If he did not, ask and I'll see if I can find it again)

Yes, this is the first thing I did, and asked him not to share on the forum as they're out of date and should not become a defacto standard. This is one of the things he meant by secrecy above.


I know it has been a while, I wonder if a more current version of protocol documentation is available anywhere? I would assume even an outdated document would be much better than nothing?

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Fri Mar 03, 2017 2:43 am
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Poor assumption.

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n00bs, do NOT PM or email tech questions! Use the forum!
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Sat Mar 04, 2017 2:52 am
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LQFP112 - Up with the play
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Fred wrote:
Poor assumption.


No worries, I can always take the longer route. Thank you for help!

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Sat Mar 04, 2017 2:59 am
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You're welcome. You need all the help you can get. :-)

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FreeEMS dev diary and its comments thread and my turbo truck!
n00bs, do NOT PM or email tech questions! Use the forum!
The ever growing list of FreeEMS success stories!


Sat Mar 04, 2017 7:23 am
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