[Ovmsdev] ELM327 codes to

Soko ovms at soko.cc
Sun Jul 26 15:22:01 HKT 2020


Hello,

Thanks heaps. There is now way I could have figured this out by myself. 
I will give your values a try asap.

You did only 3 entries for the polltime though... As far as I could see 
there are 4 which correspond to the possible parameter values for 
PollSetState(...);

Looking at the other vehicles I haven't seen any automatism the 
PollState is set by the framework. One vehicle uses 0-3 for (off, on, 
moving, charging). So I have to change the Poll-State manually in my 
vehicle implementation, correct?
In different words: When I only call PollSetState(0); (for early stage 
testing) the polling uses only the first polltime-value. Doesn't matter 
if the car os off/on/...?

thx again

Soko

On 25.07.2020 20:45, Michael Balzer wrote:
> Soko,
>
> 0x22028C isn't a PID, it's an OBD2 command (0x22 = poll extended ID) +
> the actual register address 0x028C to be polled.
>
> And 0x7E5 isn't a header, it's probably the address of the OBD2 device
> you're polling (txmoduleid) OBD2 is a subset of ISO-TP, in ISO-TP
> devices can be addressed at any ID and respond at any ID. The OBD2 base
> protocol defines a broadcast address at 0x7DF, and assigned device
> addresses in the range 0x7E0 - 0x7E7. Replies shall be sent at the
> device address + 8, so the reply for a poll to 0x7E5 would normally be
> coming from 0x7ED (rxmoduleid).
>
> That are the basic principles of the OBD2 protocol, see
> https://en.wikipedia.org/wiki/OBD-II_PIDs#CAN_(11-bit)_bus_format .
>
> So your poll could for example be defined as:
>
> const OvmsVehicle::poll_pid_t vwup_poll[] = {
>    // Note: poller ticker cycles at 3600 seconds = max period
>    // { txid, rxid, type, pid, { period_off, period_drive, period_charge } }
>    { 0x7E5, 0x7ED, VEHICLE_POLL_TYPE_OBDIIEXTENDED, 0x028C, { 0, 10, 60 } },
>    { 0, 0, 0, 0, { 0, 0, 0 } }
> };
>
> See vehicle.h for OBD2 commands (poll types) currently supported. See
> the other vehicles for examples of complex poll definitions.
>
> Regards,
> Michael
>
>
> Am 25.07.20 um 20:09 schrieb Soko:
>> Heya,
>>
>> Another thing I can't figure out at the moment. I have to poll the
>> VWeUp and I figured out (hopefully) how to do that. But I have no clue
>> how to translate the "usual" ELM327 Header+PID to one entry for the
>> OvmsVehicle::poll_pid_t
>>
>> The only value I've understood is the polltime. On my OBD2 interfaces
>> I use a PID of 0x22028C for SoC. But PID is here only 16 bit! Where do
>> I put the header 7E5? What is txmoduleid and rxmoduleid?
>>
>> I can't believe that I'm the first one with this issue ;) Couldn't
>> find any doc though :(
>>
>> So I'm very thankful for any pointing in the correct
>> direction/doc/example.
>>
>> thanks
>>
>> Soko
>>
>>
>>
>> _______________________________________________
>> OvmsDev mailing list
>> OvmsDev at lists.openvehicles.com
>> http://lists.openvehicles.com/mailman/listinfo/ovmsdev



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