Inverter control CAN frame

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ElMaco
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Inverter control CAN frame

Post by ElMaco »

Hi,
I am converting my Curtis ET-134 FNR-throttle-combo to CAN.

Looking at the documentation of the CAN frame, I get a little confused.
https://openinverter.org/wiki/CAN_commu ... _CAN_-_new!
Does e.g. pot, that ranges over one-and-a-half byte, go straight msb->lsb or does it follow the general rule with little endian. When it says that pot is bit 0:11, it sounds to me like it's straight msb->lsb. But then there is the general rule. Which is dominant and apply here?

Tried to illustrate my question with a table.
image.png
50 ft slow boat with Nissan LEAF EM-57, OI gen 2. FW 5.35. Dual (2P) KIA Eniro 64kWh (98S), Orion BMS2.
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johu
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Re: Inverter control CAN frame

Post by johu »

Nice table! You could add it to the wiki.
All multi-byte values are little endian
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Re: Inverter control CAN frame

Post by ElMaco »

johu wrote: Sun Feb 01, 2026 1:12 pm Nice table! You could add it to the wiki.
All multi-byte values are little endian
Great! Before I add it to the wiki, please confirm that I got it right in this next iteration:
image.png
This masking of e.g pot is of course only true when the bits are shifted according to where they belong in each two-byte word.

I also changed the bit order, as it made more sense.

@johu, would you say this is correct, or do I need to adjust further?
50 ft slow boat with Nissan LEAF EM-57, OI gen 2. FW 5.35. Dual (2P) KIA Eniro 64kWh (98S), Orion BMS2.
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Re: Inverter control CAN frame

Post by johu »

Looks good to me :)
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