Need Help: Display Options for Speed Sensor-Free Setup on Bafang BB02

[Nikolas]

Hi everyone,

After 10 years of great service, my old black-and-white display has finally given out. I’ve always preferred riding without a speed sensor for its simplicity, so my setup constantly shows a "21 Error." With my old display, this wasn’t a problem since the motor kept running regardless of the error.

Unfortunately, the new colour display I bought shuts the motor down after a few minutes without a speed sensor signal. I’m looking for advice on the following:

1. Are there any display models that don’t shut the motor down when there’s no speed sensor signal?
2. Ideally, is there a model that also displays battery voltage while meeting the above requirement?

Thanks in advance for any suggestions!

 

[aae34]

Would be "ugly solution", but you could just fake the value sent to display for running w/o speed sensor
on bbsfw. Could use ie. the battery voltage, so it would show battery voltage instead of speed(never 0,
so display wouldn't shutdown). Would be not-so-useful on a screen that can show voltage anyway, but
cheapest displays come w/a bar that has only 5levels, so more useful for those.

Bbsfw is the free opensource option for better firmware on bbs02 and bbshd.
Available from here: GitHub - danielnilsson9/bbs-fw: Open source firmware for multiple electric bike motor controllers.

 

[Nikolas]

Would be "ugly solution", but you could just fake the value sent to display for running w/o speed sensor
on bbsfw. Could use ie. the battery voltage, so it would show battery voltage instead of speed(never 0,
so display wouldn't shutdown). Would be not-so-useful on a screen that can show voltage anyway, but
cheapest displays come w/a bar that has only 5levels, so more useful for those.

Bbsfw is the free opensource option for better firmware on bbs02 and bbshd.
Available from here: GitHub - danielnilsson9/bbs-fw: Open source firmware for multiple electric bike motor controllers.

Thanks aae34 - you are a legend :O). I am running with the programming cable only atm which is a quick and dirty solution, only issue is no headlight. To fake the battery voltage how would you connect the 5volt feed? e.g custom plugs and a soldering iron? TIA

 

[aae34]

That would be done in the firmware, so no wiring changes would be necessary.

The programming cable is also needed for flashing, so it's great that you have it
already, if you want to flash the firmware. I can help you with the change on it,
unless you're familiar w/C, and want to do it yourself.

edit: fwiw., this is the line that needs the change:

bbs-fw/src/firmware/extcom.c at master · danielnilsson9/bbs-fw

Open source firmware for multiple electric bike motor controllers. - danielnilsson9/bbs-fw

github.com

 

[Nikolas]

That would be done in the firmware, so no wiring changes would be necessary.

The programming cable is also needed for flashing, so it's great that you have it
already, if you want to flash the firmware. I can help you with the change on it,
unless you're familiar w/C, and want to do it yourself.

edit: fwiw., this is the line that needs the change:

bbs-fw/src/firmware/extcom.c at master · danielnilsson9/bbs-fw

Open source firmware for multiple electric bike motor controllers. - danielnilsson9/bbs-fw

github.com

Thanks so much for your assistance, I can run the Bafang Config Tool but thats where my knowledge stops. Please let me know what I need to do to implement the changes you discussed :O)

 

[aae34]

Ok, i'll build a version that does it for you, but you'll need to download the bbs-fw release,
as it comes with a separate tool to write the configuration you want for it.

Those options are mostly described here:

Configuration Tool

Open source firmware for multiple electric bike motor controllers. - danielnilsson9/bbs-fw

github.com

Won't have time for this until after 16:30(gmt+2), but then it shouldn't take many minutes to do.

 

[aae34]

I got to look at this already;
The change i decided to do was to comment out lines 603,604 and 629-633, so it will show
always whatever you choose in the configuration(walkmode data display; battery percent,
requested power or temperature) instead of speed defaulting to requested power.

From here you can find the instructions for flashing on windows:

Flash Firmware (BBS02 & BBSHD)

Open source firmware for multiple electric bike motor controllers. - danielnilsson9/bbs-fw

github.com

For linux there is easier option, but i'm guessing above is what you want to go with.

This link should work for downloading the modified version of bbsfw for you:
edit: it was time for me to clean the tree from unnecessary branches.

 

[Guerney]

Hi everyone,

After 10 years of great service, my old black-and-white display has finally given out. I’ve always preferred riding without a speed sensor for its simplicity, so my setup constantly shows a "21 Error." With my old display, this wasn’t a problem since the motor kept running regardless of the error.

Unfortunately, the new colour display I bought shuts the motor down after a few minutes without a speed sensor signal. I’m looking for advice on the following:

1. Are there any display models that don’t shut the motor down when there’s no speed sensor signal?
2. Ideally, is there a model that also displays battery voltage while meeting the above requirement?

Thanks in advance for any suggestions!

Run it headless?

https://www.pedelecs.co.uk/forum/threads/running-bbs01-without-display.31146/#post-435412