B0B : Battery without BMS ;-)

[MossFromIt]

You can use it with all the benefits of firmware 400 + 500.
Firmware 400 allows to program batt type to 0,2 or 3 (no RTH on low batt).
On top of it you can install the camera module of firmware 500. (This is 'module mixing' method).
But you cannot use B0B, directly with firmware 500...

Do you know what is the tricky part that prevents DIY battery?
If we can intercept the firmware during battery firmware update then put it on a copied board. Is it doable?

 

[everBit]

Do you know what is the tricky part that prevents DIY battery?

Proprietary authentication protocol based on latest cryptoalgorythms.

If we can intercept the firmware during battery firmware update then put it on a copied board. Is it doable?

No. You could intercept hole update image but you could not use it to copy to blank IC.
Update is done through proprietary loader using cryptocontainer so new IC should as minimum be preprogrammed with that DJI loader.

Even if someone manages to do that step the battery would be rejected by the drone as counterfait because without private hashing keys which are preprogrammed at the factrory to OTP secure memory the IC will fail to authenticate. Those keys are not the part of the firmware and so could not be copied.

 

[MossFromIt]

No. You could intercept hole update image but you could not use it to copy to blank IC.
Update is done through proprietary loader using cryptocontainer so new IC should as minimum be preprogrammed with that DJI loader.

Even if someone manages to do that step the battery would be rejected by the drone as counterfait because without private hashing keys which are preprogrammed at the factrory to OTP secure memory the IC will fail to authenticate. Those keys are not the part of the firmware and so could not be copied.

Thanks for the explanation, much clear now. Unless we can read the OTP or know the hashing keys.
Looks like the only way to use 500 firmware is to upgrade the 18650 cells from an original battery pack.

 

[everBit]

there are still first batch batteries on the market made in October and November of 2019.
They are on the v100 firmware and allow to recell them to another 18650 by cold-swap method.
Then one could use them in the v500 upgraded drone.

Alternatevly it's still possible to hot-swap the cells on the v500 batteries though the job should be done very accurately not loosing the power to pcb.

Some workshops first downgrade v500 batteries to v100, then recell, then upgrade or left with v100 as is to make possible further recelling by customer. It will throw upgrade notification in the app which though could be ignored.
This method requires additional programming tools.

 

[MossFromIt]

I got the necessary skill for hot-swapping, will try if I can find some good broken batteries.

But those V100 batteries are extremely difficult to find. Downgrade then upgrade make no sense if we can just hotswap.

There is a batch of cheap batteries for Japan's version (around half price). Not sure if we can do something on them

 

[everBit]

Japanese versions are preprogrammed for 4.4V LiHV and the half of capacity so they should first be reprogrammed for CE 4.2V LION 2400mAh version, this case we will lose the benefits of stock price as reprogramming also costs some penny.

'just hotswap' is easy to say), it's some sort of jewelry work, if power is loosed even for the moment then bms is bricked.

 

[MossFromIt]

Japanese versions are preprogrammed for 4.4V LiHV and the half of capacity so they should first be reprogrammed for CE 4.2V LION 2400mAh version, this case we will lose the benefits of stock price as reprogramming also costs some penny.

'just hotswap' is easy to say), it's some sort of jewelry work, if power is loosed even for the moment then bms is bricked.

I am trying to get some cheap batteries since I only have one currently. I don't really mind 25 min or 35 min for a bat.
The JNP version is cheap, but if there is space, it would be better if I can replace some HV cells to extend some flight time to get around 20+ min will be great. Just a thought.

I am an embedded/hardware engineer, so that is where all the thoughts came from.

 

[vadda]

You can use it with all the benefits of firmware 400 + 500.
Firmware 400 allows to program batt type to 0,2 or 3 (no RTH on low batt).
On top of it you can install the camera module of firmware 500. (This is 'module mixing' method).
But you cannot use B0B, directly with firmware 500...

is it possible to have the functionality of the propeller / motor control that warns if the propellers are deformed , with the FW mix system ?
I seemed to understand that, starting from the FW .400, it is possible to include in the upgrade to the FW .500 even the module 000 and 0100 (with Drone-Hack app) but I did not understand in which module the part of the control on the engine revolutions resides, the one that says if the propellers must be replaced.
Does this feature stay with this FW Mix?

 

[aeropic]

is it possible to have the functionality of the propeller / motor control that warns if the propellers are deformed , with the FW mix system ?
I seemed to understand that, starting from the FW .400, it is possible to include in the upgrade to the FW .500 even the module 000 and 0100 (with Drone-Hack app) but I did not understand in which module the part of the control on the engine revolutions resides, the one that says if the propellers must be replaced.
Does this feature stay with this FW Mix?

I am quite sure the propellers feature does not remain activated with modules 000 and 100. Because the module which is kept is the camera module only...

 

[aeropic]

I am trying to get some cheap batteries since I only have one currently. I don't really mind 25 min or 35 min for a bat.
The JNP version is cheap, but if there is space, it would be better if I can replace some HV cells to extend some flight time to get around 20+ min will be great. Just a thought.

I am an embedded/hardware engineer, so that is where all the thoughts came from.

I also own only one genuine batt...
I follow your discussions on hot swapping batts with the genuine BMS. Of course it works but with the risk to fail the jewelry process and brick your board...
B0B is designed only for the purpose to try any battery you wish (Lipo, LIHV, big Li ion...) everything is working with it. it is a sandbox for batteries ;-)

 

[vadda]

Any info about parameters "enable_new_smart_battery" and "g_status.battery.raw_info.capacity_percentage" ?

 

[aeropic]

Any info about parameters "enable_new_smart_battery" and "g_status.battery.raw_info.capacity_percentage" ?

No sorry... I don't know what they do...

 

[everBit]

and "g_status.battery.raw_info.capacity_percentage"

Just a guess, some modders managed to change battery charge display in the app from percentage to total voltage, may be this setting is for that.

 

[aeropic]

Just a guess, some modders managed to change battery charge display in the app from percentage to total voltage, may be this setting is for that.
View attachment 109153

Is this for the mini ?
Anyway, on the DJI fly the percent of charge is an information computed either by the firmware or by the application. It is based upon a combination of remaining percent of charge know by the BMS and the voltage. (B0B is generating those parameters)...

 

[everBit]

it's for older brother but some parameters could be migrated to Mini as well.

 

[zaninio]

Is this for the mini ?
Anyway, on the DJI fly the percent of charge is an information computed either by the firmware or by the application. It is based upon a combination of remaining percent of charge know by the BMS and the voltage. (B0B is generating those parameters)...

Hi if i put the 400 firmware then which program i have to use to change the parameters battery to 0 to avoid the auto landing? thank you

 

[aeropic]

Hi if i put the 400 firmware then which program i have to use to change the parameters battery to 0 to avoid the auto landing? thank you

Drone-hacks.exe will do the job !

 

[zaninio]

Drone-hacks.exe will do the job !

Thank you!! i downgrade to 400 i open the drone hack but i can't change the battery parameters i don't know how can you give me a little help?

 

[aeropic]

Thank you!! i downgrade to 400 i open the drone hack but i can't change the battery parameters i don't know how can you give me a little help?

First connect your drone (disconnect the USB, switch on the drone, after the tone scheme connect the drone. It should be recognized by DH. if not do it agin after having removed the SD card.

Once connected, just click on parameters tab, then click on advanced parameters. Then on the search field type "BATT" and you should see B"ATT-type"
tuto here: https://youtu.be/96oaoMC_Zkw

 

[zaninio]

First connect your drone (disconnect the USB, switch on the drone, after the tone scheme connect the drone. It should be recognized by DH. if not do it agin after having removed the SD card.

Once connected, just click on parameters tab, then click on advanced parameters. Then on the search field type "BATT" and you should see B"ATT-type"
tuto here: https://youtu.be/96oaoMC_Zkw

thank you i do all this i change the battery type value to 0 but not any button to SAVE changes!! i have to install and the moded firmware for changing the parameters?? or i do something wrong?