Why do I have these CAN mappings on 0x3F  [SOLVED]

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OtterTech
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Why do I have these CAN mappings on 0x3F

Post by OtterTech »

TLDR: I'm quite new to this whole thing and I noticed my CAN mappings on ID 63 (0x3F) are not the same as in the wiki. What went wrong?

I recently started working on a projekt involving the openinverter board for the Tesla LDU and full CAN controll. naturally I looked up the CAN mapplings and found that ID 0x3F has a fixed mapping with all relevant controll signals as lined out in the wiki. But sending the commands cause the inverter to drop CAN communication.
Thanks to the openinverter-can-tool I was able to save the current active mappings and open them in Savvy-CAN. This is where I first found the descrepancy. The ESP-32 web GUI does not show any can mappings.
I would expect the mappings to match the mappings from the wiki but I got the following:
pot, pot2 and canio are the same as expected. Byte 4 bit 0 to 5 are the CAN speed (0x00=125k, 0x01=250k, 0x02=500k, 0x03=800k, 0x04=1M). The cruisespeed parameter is not available for me.
Both canrun fields are still checked and cancrc is also checked but I have not yet been able to correctly generate the crc-code.

Sending 0x02 as byte 4 has resolved the connection issues as the CAN-speed now stays at 500k. I have also been able to send pot values that are received by the inverter.

The first thing after finding a descrepancy between the CAN-Mappings was for me to update the inverter once again with a redownloaded 5.40-sine firmware but it did not change anything.
Digging a bit into the code I found that the mapping is hard coded to the CAN-ID as outlined on the wiki. This makes it even more confusing than it already is for a new setup.
One minor bug I found along the way: Version 5.40 reports as version 5.39 in the web GUI as it is defined in the code.

Now to my question: What have I done to break my CAN mappings in this way?
I will collect possible solutions and answer questions I'm able to until the 5th March when I will be at the shop with the Motor and inverter again.
OtterTech
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A small update on the situation

Post by OtterTech »

After a reset of the stm via the oic-can-tool the webinterface shows the mapping of canspeed again. During the first use I deleted this mapping therefore it was not shown in the GUI.
I laso have some trouble with the web interface as I more often than not get "Communication problem between ESP and STM" in the red banner at the top of the page.

Also no real motor spin yet. Performance inverter spun with about 2 °/s whilst drawing 20 A at 4 V (powersupply was set to 48 V), Base inverter does neither spin nor draw current.
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johu
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Re: Why do I have these CAN mappings on 0x3F  [SOLVED]

Post by johu »

The 0x3f message isn't a "traditional" CAN mapping but as you already noticed a fixed one on the inverter side. So it will not show up in CAN maps and if it does should be deleted and saved to flash.
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OtterTech
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Re: Why do I have these CAN mappings on 0x3F

Post by OtterTech »

I deleted the mapping and now things work better than before. I still don't know how they got there, epecially since the board was never used when I started.
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