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Michael,<br>
<br>
the obdii command's broadcast feature isn't capable of processing
multiple responses, maybe that's what happens. It's more meant as a
ping to see if there are some SAE conforming devices on the bus.<br>
<br>
Don't expect to detect specialized devices by a broadcast, only some
devices acting in the standard SAE/OBDII ID range (7E0-7E7) will
listen to the broadcast ID. To find ISO-TP devices not conforming to
the SAE ID range, you need to loop over the probable TX ID range,
e.g. 500-7FF (make sure there are no process data frames present in
that range first). Looping over an ID range is currently best done
using a script, the re scan tool lacks this option.<br>
<br>
Most EV do not implement standard SAE OBDII PIDs, so querying the
VIN by 0902 normally doesn't work (see other vehicle modules for
some examples). Most EV don't even comply to the OBDII standard of
giving you bitsets of supported PIDs.<br>
<br>
But as you see a response, try sending the request to the device the
response corresponds to (i.e. response ID - 8). The VIN should
normally be on device 7E0 7E8. It's also totally normal the devices
only respond while the car is on, awake or charging. Finding out how
to wake up a car from OBD is one of the hard parts.<br>
<br>
Finally, if the vehicle currently loaded doesn't implement a full
shutdown (happens when switching to another vehicle like NONE), you
may end up with partially initialized CAN interfaces or other
strange issues. To make sure the vehicle module doesn't interfere
with your scans, boot into vehicle NONE.<br>
<br>
Regards,<br>
Michael<br>
<br>
<br>
<div class="moz-cite-prefix">Am 20.09.22 um 08:26 schrieb Michael
Geddes:<br>
</div>
<blockquote type="cite"
cite="mid:CAH0p7uLazALuOHvSHG66=6ruttVvX9-saQYcdtrBQhtw4WuRjQ@mail.gmail.com">
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<div dir="ltr">Hi all,
<div>I have got my OVMS device (no SIM yet, but I'm working on
that), and have been connecting and playing round with
commands.</div>
<div><br>
</div>
<div>I'm starting to get my head around things. I have being
mucking round with SavvyCan and now understand a little the
ISO-TP protocol stuff happening on top of the standard can bus
now. SavvyCan seems to like disconnecting from the TCP
server, but going via a COM emulator seems to work better (and
can be restarted). All very weird, but I can cope with that.</div>
<div><br>
</div>
<div>I'm getting a weird response from the following when it
responds (VIN):</div>
<div>obdii can1 request broadcast 0902<br>
</div>
<div>
<p
style="line-height:100%;margin-bottom:0cm;background:transparent">It
contains elements of my actual VIN but not the main number
at the end. I'm wondering if this is an OBDII receive
issue? Does this command work for other people to get the
actual VIN? Also it seems to only work in certain
circumstances (?when the car is on?).. which is "fun".</p>
<p
style="line-height:100%;margin-bottom:0cm;background:transparent"><span
style="background-color:transparent">I have also had
issues where if I use the "Set Car to NONE" on the RE PID
Scanner interface, it seems to stop communications.. and </span>obdii<span
style="background-color:transparent"> command set no
longer works - even if I restart the CAN bus. Setting the
vehicle back to 'KO' seems to fix things.</span></p>
<p
style="line-height:100%;margin-bottom:0cm;background:transparent">//.ichael
Geddes</p>
</div>
</div>
</blockquote>
<br>
<pre class="moz-signature" cols="72">--
Michael Balzer * Helkenberger Weg 9 * D-58256 Ennepetal
Fon 02333 / 833 5735 * Handy 0176 / 206 989 26</pre>
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