IMAX B6 charger (original and clone) - open source firmware

HC1969 · Post by **HC1969** » Sat Nov 09, 2013 4:18 pm

I found a very interesting development!

A well-known open-source battery charger tuning!
Origin forum:
http://www.rcgroups.com/forums/showthre ... st26420111

Open source (origin):
https://github.com/stawel/cheali-charger

Modifications improved:
https://github.com/njozsef/cheali-charger-test1

flash tutorial for imax charger:
[BBvideo 425,350]http://www.youtube.com/watch?v=RZIxq7Pb53A[/BBvideo]

Schematic diagram:
http://elektrotanya.com/rc-power_bc6_im ... nload.html

rperkins · Post by **rperkins** » Sat Nov 09, 2013 5:30 pm

neat
looks like they added my accucell 6 a couple weeks ago.

Now to decide
+ internal resistance of batteries measurement
+ nice graphics
- My charger is meeting my needs right now
- Dont want to mess it up and have to buy another one
- probably ought to finish a couple other things before starting another one

thanks for posting about this

Post by **jhsa** » Sat Nov 09, 2013 7:27 pm

hey, I have one of those.. will read the links carefully..

I have also the imaxb6 without the power supply and it seems not to be very accurate..

Thanks for posting it..

João

njozsef · Post by **njozsef** » Mon Dec 09, 2013 10:09 am

update:
- reduced hexfiles (50W, 200W, 400W, 200Wx2-commondisplay)
- protect uncalibrated charger.
- other minor fix. (overflow check, protect charger smps circuit)
- calibration error check

future:
-eeprom editor (need ISP connector)
-manual

Hi Guys.

New features:
- new Li-ion 4.35V Charge voltage supported. Battery codename: Li43
- cyclecharging with waste-time (working). This is long-long test

- cyclehistory screen working.

tested hexfiles on:
https://github.com/njozsef/cheali-charg ... master/hex

Post by **jhsa** » Sun Nov 08, 2015 1:50 pm

Hi I didn't want to mess with my chargers as they are working well, but now I got one from a friend that did set one of his packs on fire and nearly burnt his house down. I could make tests with this one and maybe fix it. I think a bad calibration could have caused the charger to overchatge his battery?
Anyway, I could use this one to try the open source firmware. Need to find another way to calibrate the individual balance outputs as I don't have a 6 cell lipo pack.
Can't they be calibrated individually? If not is there a circuit we can build with resistors/pots to connect a power supply and calibrate the 6 balance outputs?

Thanks

João

OctavioS · Post by **OctavioS** » Sun Nov 08, 2015 5:18 pm

They have 2 "secret" menu that you can calibre the voltage, wether if it's overcharging or not charging completely, but it's limited. One of the menus can be accessed only once. Search in youtube.

Enviado do meu Galaxy S6 edge através de Tapatalk.

Post by **jhsa** » Sun Nov 08, 2015 5:21 pm

yeah, I know.. I was referring to the new open source firmware.. I guess I'd better try posting on the main development thread, on RCG I think..

João

OctavioS · Post by **OctavioS** » Sun Nov 08, 2015 5:32 pm

Definitely.

Enviado do meu Galaxy S6 edge através de Tapatalk.

Koarl · Post by **Koarl** » Sun Nov 08, 2015 10:06 pm

It would be nice when the firmware would enable the charger to be used as foamcutter. Is that possible?

OctavioS · Post by **OctavioS** » Mon Nov 09, 2015 2:12 pm

No man, but I read somewhere that there is firmware that turns in to a baking machine.

Enviado do meu Nexus 7 através de Tapatalk

Post by **Kilrah** » Mon Nov 09, 2015 3:06 pm

Some of these chargers actually do have a foam cutter drive mode, which basically makes it into a CC/CV "lab" power supply.

Koarl · Post by **Koarl** » Mon Nov 09, 2015 3:51 pm

Yeah, there are some. But my b6 hasn't that function.

Post by **jhsa** » Mon Nov 09, 2015 4:10 pm

I don't think the B6 could do it. it's only 5A maximum current.. or would that be enough?

João

OctavioS · Post by **OctavioS** » Mon Nov 09, 2015 5:50 pm

Kilrah wrote:Some of these chargers actually do have a foam cutter drive mode, which basically makes it into a CC/CV "lab" power supply.

Oops, I thought he was joking with that foam cutter issue.
My apologies.

Enviado do meu Galaxy S6 edge através de Tapatalk.

Koarl · Post by **Koarl** » Mon Nov 09, 2015 6:25 pm

And it wasn't funny.

@jhsa:
Never measured the current on my diy foamcutter. I only now the voltage, it's around 20Volts

KAL · Post by **KAL** » Mon Nov 09, 2015 6:34 pm

The required voltage depends on the length of the resistance wire.
Current is what counts (in fact it's the wattage).

Edit: 5A should be more than sufficient. up to 3,5A should be enough most of the time ...

Klaus

Koarl · Post by **Koarl** » Wed Nov 11, 2015 8:07 am

Exactly! But as I said I never measured the current. I have a poti to regulate the heat.

Koarl · Post by **Koarl** » Sat Nov 14, 2015 4:40 pm

Would you think that it's possible to flash the charger with companion or is it necessary to fiddle around with this avrdude interfaces.

Post by **Kilrah** » Sat Nov 14, 2015 5:31 pm

You need the command line, companion does not have a preset for the processor types used there as they aren't the same as on any of the 9x variants.

Not that hard to do a copy/paste though...

Koarl · Post by **Koarl** » Sat Nov 14, 2015 11:13 pm

Ok, thanks! Maybe I'll give it a try...

Gesendet von meinem iPad mit Tapatalk

Post by **MikeB** » Sat Nov 14, 2015 11:54 pm

If you have multiple -p options on the command line, I believe Avrdude only uses the last one. So, if you put an extra argument of "-p m32" in the companion communication menu you should be able to run Avrdude from companion.

Mike.

Koarl · Post by **Koarl** » Mon Nov 16, 2015 1:30 pm

I just opened the programmer to see how things look. I just slid the charger open like in the video and damaged all the buttons. I highly recommend to push the buttons out with a small srewdriver before sliding the charger open!

Then I read through the calibration manual there a question occured:
How is the power supply voltage input calibrated when the charger is an AC/DC device? Powering it with a car battery and measure the battery's voltage?

Koarl · Post by **Koarl** » Mon Nov 16, 2015 3:40 pm

Now I have tried to flash my Imax B6 AC genuineusing avrtools, but now it just shows squares. I tried to flash it back to the original firmware I read from the charger, but the problem stays the same.

avrtools gives me this output:

avrdude: verifying …
avrdude: verification error, first mismatch at byte 0x33ad
0xd6 != 0x00
avrdude: verification error; content mismatch

I hope someone can help me please!

Thanks!

Post by **jhsa** » Mon Nov 16, 2015 3:44 pm

Can ypu post the complete output from avrdude?

Koarl · Post by **Koarl** » Mon Nov 16, 2015 4:00 pm

Thanks for your answer!

Here we go!

[ Task runtime: 35.385 seconds ]
-c usbasp -p m32 -P /dev/cu.Bluetooth-Serial-1 -B 8.68 -U flash:w:/Users/carloskammerlander/Desktop/imax dump/avrFlashFile.hex -U eeprom:w:/Users/carloskammerlander/Desktop/imax dump/avrEepromFile.hex

avrdude: set SCK frequency to 93750 Hz
avrdude: AVR device initialized and ready to accept instructions

Reading | ################################################## | 100% 0.01s

avrdude: Device signature = 0x1e9502
avrdude: NOTE: FLASH memory has been specified, an erase cycle will be performed
To disable this feature, specify the -D option.
avrdude: erasing chip
avrdude: set SCK frequency to 93750 Hz
avrdude: reading input file "/Users/carloskammerlander/Desktop/imax dump/avrFlashFile.hex"
avrdude: input file /Users/carloskammerlander/Desktop/imax dump/avrFlashFile.hex auto detected as Intel Hex
avrdude: writing flash (32766 bytes):

Writing | ################################################## | 100% 24.13s

avrdude: 32766 bytes of flash written
avrdude: verifying flash memory against /Users/carloskammerlander/Desktop/imax dump/avrFlashFile.hex:
avrdude: load data flash data from input file /Users/carloskammerlander/Desktop/imax dump/avrFlashFile.hex:
avrdude: input file /Users/carloskammerlander/Desktop/imax dump/avrFlashFile.hex auto detected as Intel Hex
avrdude: input file /Users/carloskammerlander/Desktop/imax dump/avrFlashFile.hex contains 32766 bytes
avrdude: reading on-chip flash data:

Reading | ################################################## | 100% 16.43s

avrdude: verifying …
avrdude: verification error, first mismatch at byte 0x33ad
0xd6 != 0x00
avrdude: verification error; content mismatch

avrdude done. Thank you.

[ Task runtime: 35.390 seconds ]

Koarl · Post by **Koarl** » Mon Nov 16, 2015 4:10 pm

It works again, I used the file in the attachment.

Edit:
Now I can enter the calibration menu but how do I run the CORRECT(!) firmware for my charger that enables all these cool extra functions? I have already surfed to the github site, but I don´t know which fw I should coose and how get a flashable hex file from these funny "matrix codes".

Any advice is appreciated!

Thanks

Post by **jhsa** » Mon Nov 16, 2015 4:23 pm

Try the RCG forum linked on the first post.. I still didn't look into this. I'm busy with something else. I got a charger from a friend that normally would end in the rubbish and that will allow me to mess with it without experimenting with my working ones..
I'm looking into a way of calibrating all the cell outputs. maybe with a power supply and some voltage dividers made with resistors and pots..

João

Koarl · Post by **Koarl** » Mon Nov 16, 2015 4:28 pm

Thanks, I will do so!

jhsa wrote: I got a charger from a friend that normally would end in the rubbish and that will allow me to mess with it without experimenting with my working ones..

That is very wise, should have done the same!

jhsa wrote: I'm looking into a way of calibrating all the cell outputs. maybe with a power supply and some voltage dividers made with resistors and pots..

João

Sounds nice! Keep us tuned please!

Koarl · Post by **Koarl** » Mon Nov 16, 2015 5:37 pm

Do you mean like so?
http://www.martinmelchior.be/2013/09/re ... arger.html

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