Bratitude wrote: ↑Fri Oct 23, 2020 4:30 am
in theory it should be possible to add a additional gen1 volt slave onto the Chevy volt bms train? Or is the teensy 3.2 almost out of address space at this point?
I’d like to possibly add an additional cell group to the pack, increasing storage and voltage without paralleling two full packs.
It's not an issue of the Teensy - you'll hit into CAN address collisions as they are fixed IDs as I understand it. (I've yet to wire mine up )
The Teensy is certainly powerful enough for the tasks assigned to it.
Bratitude wrote: ↑Fri Oct 23, 2020 4:30 am
in theory it should be possible to add a additional gen1 volt slave onto the Chevy volt bms train? Or is the teensy 3.2 almost out of address space at this point?
I’d like to possibly add an additional cell group to the pack, increasing storage and voltage without paralleling two full packs.
It's not an issue of the Teensy - you'll hit into CAN address collisions as they are fixed IDs as I understand it. (I've yet to wire mine up )
The Teensy is certainly powerful enough for the tasks assigned to it.
-Matt
Correct, nearly all OEM Canbus systems have fixed IDs, or atleast a fixed number for IDs you can assign (BMW).
So usually this would mean you are limited to a MAX amount of slaves in the original pack, you can always run less if you want.
Bratitude wrote: ↑Fri Oct 23, 2020 4:30 am
in theory it should be possible to add a additional gen1 volt slave onto the Chevy volt bms train? Or is the teensy 3.2 almost out of address space at this point?
I’d like to possibly add an additional cell group to the pack, increasing storage and voltage without paralleling two full packs.
It's not an issue of the Teensy - you'll hit into CAN address collisions as they are fixed IDs as I understand it. (I've yet to wire mine up )
The Teensy is certainly powerful enough for the tasks assigned to it.
-Matt
Correct, nearly all OEM Canbus systems have fixed IDs, or atleast a fixed number for IDs you can assign (BMW).
So usually this would mean you are limited to a MAX amount of slaves in the original pack, you can always run less if you want.
right, of course. in that case I’d run a second teensy with the additional cell group in series to the pack.
Bratitude wrote: ↑Fri Oct 23, 2020 4:30 am
in theory it should be possible to add a additional gen1 volt slave onto the Chevy volt bms train? Or is the teensy 3.2 almost out of address space at this point?
I’d like to possibly add an additional cell group to the pack, increasing storage and voltage without paralleling two full packs.
If I remember correctly, no because of the way the Chevy BMS slaves are addressed.
EDIT: Thought I posted this before the other replies, did not mean to be redundant
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It's not an issue of the Teensy - you'll hit into CAN address collisions as they are fixed IDs as I understand it. (I've yet to wire mine up )
The Teensy is certainly powerful enough for the tasks assigned to it.
-Matt
Correct, nearly all OEM Canbus systems have fixed IDs, or atleast a fixed number for IDs you can assign (BMW).
So usually this would mean you are limited to a MAX amount of slaves in the original pack, you can always run less if you want.
right, of course. in that case I’d run a second teensy with the additional cell group in series to the pack.
May I suggest that the use of an extra CAN-controller+tranceiver should do the trick. No need for an extra micro controller.
right, of course. in that case I’d run a second teensy with the additional cell group in series to the pack.
May I suggest that the use of an extra CAN-controller+tranceiver should do the trick. No need for an extra micro controller.
If you want to re write the code to do this, feel free to do so.
Reading my post above again I realize that it did not come out right.
I do not have the knowledge to re write the code. I was only trying to suggest that it could be done with another CAN-controller but the firmware have to be adjusted accordingly.
I think what is done here is great, but even so, it can be improved further.
bexander wrote: ↑Sat Oct 24, 2020 4:46 am
Reading my post above again I realize that it did not come out right.
I do not have the knowledge to re write the code. I was only trying to suggest that it could be done with another CAN-controller but the firmware have to be adjusted accordingly.
I think what is done here is great, but even so, it can be improved further.
Ofcourse anything can be improved and changed to meet different requirements. This is why I am working, all be it slowly, on a V3 with 3 can busses.
Has anyone had an issue with charge input not working, I have 12v in J5 pin 6 but nothing comes up on input in debug. Not sure if I've set something up wrong, no errors and input for drive mode works fine.
Thanks Tom, on a closer look I found the opto coupler had a dry joint. I've resoldered and flashed the latest firmware. I'll hopefully be able to test after work tonight. (Australia time)
I noticed in Dusty4's output the same thing I see - 0V for middle cells...Is this a known issue? And is it simply ignored by the ignore cell with voltage less than threshold setting?
mdrobnak wrote: ↑Mon Nov 09, 2020 10:15 pm
I noticed in Dusty4's output the same thing I see - 0V for middle cells...Is this a known issue? And is it simply ignored by the ignore cell with voltage less than threshold setting?
The reason for this is purely down to can decoding. I do not map it exactly but do it as "simple" as possible. Some slaves might skip one or two fields and leave those at "0.0 V", but not to worry the code does not care as long as your cell count says the amount of cells connected you are fine.
Hey Tom, I've got it hooked up again and inputs work correctly now . I've got a problem with the tc charger I'm using, the bms is in charge mode, plug in the charger and I get red,green,red led (bad communication). I see in the serial terminal the expansion module is set to 500kbps (I'm unable to change it) and the charger has the option of 250kbps or 500kbps. I'm not sure what the charger would be set at, and I got very little documentation with it. What is your thought?
Dusty4 wrote: ↑Sat Nov 14, 2020 11:06 am
Hey Tom, I've got it hooked up again and inputs work correctly now . I've got a problem with the tc charger I'm using, the bms is in charge mode, plug in the charger and I get red,green,red led (bad communication). I see in the serial terminal the expansion module is set to 500kbps (I'm unable to change it) and the charger has the option of 250kbps or 500kbps. I'm not sure what the charger would be set at, and I got very little documentation with it. What is your thought?
What are your charger settings? Do you have any can sniffer tool to check the data coming out of the charger without the bms attached, you just need to give it AC voltage for it to start spitting out canbus.
I do not recall still having an issue with a canbus expansion module, are you on the latest firmware?
Good news Tom, This morning I've plugged the CAN module into a serial adaptor and I was able to change the baud rate to 250kbps, I was then able to change the expansion setting in the serial terminal to 250kbps. Connected it all up and it's happily charging Thanks for your help
sorry to be a pain Tom, my display isn't displaying any data from the BMS. how can I check if the BMS is sending anything? Or would it be worth reflashing the display?
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. I've got a problem with the tc charger I'm using, the bms is in charge mode, plug in the charger and I get red,green,red led (bad communication). I see in the serial terminal the expansion module is set to 500kbps (I'm unable to change it) and the charger has the option of 250kbps or 500kbps. I'm not sure what the charger would be set at, and I got very little documentation with it. What is your thought?
Thanks for your help