KT motor controllers -- Flexible OpenSource firmware for BMSBattery S/Kunteng KT motor controllers (0.25kW up to 5kW)

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stancecoke   10 kW

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Re: KT motor controllers -- Flexible OpenSource firmware for BMSBattery S/Kunteng KT motor controllers (0.25kW up to 5kW

Post by stancecoke » Jul 15 2018 2:34pm

1N4001 wrote:
Jul 15 2018 2:13pm
Ok, so I am finally trying to build the firmware on Linux.
I can't help with linux. I 've tried it, see the very first pages of this thread, but I despaired after several days :shock:

Good luck :-)

regards
stancecoke

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Re: KT motor controllers -- Flexible OpenSource firmware for BMSBattery S/Kunteng KT motor controllers (0.25kW up to 5kW

Post by casainho » Jul 15 2018 3:26pm

sdcc - compiler: stm8-binutils-gdb claims that "From version 2018-03-04 sdcc and openocd for stm8 does no longer have to be patched" and "The latest version of SDCC is 3.7.0 and support debugging with dwarf2 format". So I suppose I'll be needing v3.7.0 then? Or does stm8-binutils-gdb already come with sdcc?[/quote]
I think you should foow the instructions of stm8binutils site and then they point you to build and install sdcc 3.7.0.
I use sdcc 3.7.0.
1N4001 wrote:
Jul 15 2018 2:13pm
OpenOCD - debugger?: As with sdcc, it needs a newer version for compatibility with stm8-binutils-gdb. The latest release is 0.10.0 from Jan 2017. I guess I'll have to compile the newest sources then?
I use and built the 0.10.0. You can look at build examples for STLinkv2, which is very popular.

[quote=1N4001 post_id=1395187
stm8-binutils-gdb - toolchain??: As far as I can tell, this is a toolchain patchset for stm8 support. But then shouldn't gdb be the debugger? What's openocd for?


- flasher: Do I even need this? According to the docs page: "tools like OpenOCD that will let you flash and debug the firmware"
[/quote]
If you look online for flash and debug ARM with OpenOCD, JTAG and Eclipse, for STM8 is just the same workflow and tools.

If you are on Windows amd just want to build the firmware, then follow Stancecoke guide. On Linux you get plus developer tools like JTAG debug.
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If you like my work, you can consider making a donation. I am being using the donations to buy needed resources for my developments. My paypal: casainho AT gmail.com.

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Re: KT motor controllers -- Flexible OpenSource firmware for BMSBattery S/Kunteng KT motor controllers (0.25kW up to 5kW

Post by casainho » Jul 15 2018 10:47pm

stancecoke wrote:
Jul 15 2018 12:24pm
I know and understand your implementation. Perhaps I will copy it, if the first useres report burned mosfets with my solution... :wink:

The control loop doesn't allow high gradients in duty cycle anyway. The biggest risk is to block the wheel while braking hard at riding, so you should avoid this.
I think some users here want fast throttle response and use the version of higher power KT controllers, so is a must to have the implementation I did. But I understand if you are limited of time to implement it.
stancecoke wrote:
Jul 15 2018 12:24pm
casainho wrote:
Jul 15 2018 12:12pm
That seems an incorrect implementation because:
This implementation is not incorrect, it's based on the theory of "phase current = battery current / dutycycle", not on the measured battery current. It limits the target-value for battery- and phase current. So we will never set a current target, that's critical for the motor or the mosfets.
I should had use better words. Sure it is correct but will fail (probably burning the mosfets). In fact, I am using just that on TSDZ2 firmware because the hardware of TSDZ2 motor controller can't read motor phase current unlike KT but that is probably because TSDZ2 motor is not so powerful as some motors run by KT controllers and also TSDZ2 motor must be configured to accelerate slower...
Developer of the Flexible OpenSource firmware for EBike motor controllers (TSDZ2 and KT) and LCDs (KT-LCD3 and Bafang 850C color LCD).

If you like my work, you can consider making a donation. I am being using the donations to buy needed resources for my developments. My paypal: casainho AT gmail.com.

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Re: KT motor controllers -- Flexible OpenSource firmware for BMSBattery S/Kunteng KT motor controllers (0.25kW up to 5kW

Post by casainho » Jul 15 2018 10:51pm

stancecoke wrote:
Jul 15 2018 7:31am
honya96 wrote:
Jul 15 2018 6:21am
Do you plan to show the temp on lcd3? I can order one for you if you will implement NTC10K, KTY 83, KTY 84 sensors.
I don't use any display. Perhaps Casainho can implement it in his custom firmware for LCD3. Of course we have to send the temperature data from controller side. I can implement it, if Casainho tells me the needed bytes in the communicatian protocol. :D
Sorry but I can't implement support for KT controllers on LCD3, because of time limitations. But I accept pull requests/contributions from others that want to make support for KT firmware.
Developer of the Flexible OpenSource firmware for EBike motor controllers (TSDZ2 and KT) and LCDs (KT-LCD3 and Bafang 850C color LCD).

If you like my work, you can consider making a donation. I am being using the donations to buy needed resources for my developments. My paypal: casainho AT gmail.com.

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Re: KT motor controllers -- Flexible OpenSource firmware for BMSBattery S/Kunteng KT motor controllers (0.25kW up to 5kW

Post by honya96 » Jul 16 2018 2:03am

casainho wrote:
Jul 15 2018 10:51pm
stancecoke wrote:
Jul 15 2018 7:31am
honya96 wrote:
Jul 15 2018 6:21am
Do you plan to show the temp on lcd3? I can order one for you if you will implement NTC10K, KTY 83, KTY 84 sensors.
I don't use any display. Perhaps Casainho can implement it in his custom firmware for LCD3. Of course we have to send the temperature data from controller side. I can implement it, if Casainho tells me the needed bytes in the communicatian protocol. :D
Sorry but I can't implement support for KT controllers on LCD3, because of time limitations. But I accept pull requests/contributions from others that want to make support for KT firmware.
Lcd3 can show the temp with stock FW, I don't want to mess with the lcd FW..

But I understand that if someone needs it, he has to implement it... :roll:

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Re: KT motor controllers -- Flexible OpenSource firmware for BMSBattery S/Kunteng KT motor controllers (0.25kW up to 5kW

Post by stancecoke » Jul 16 2018 2:17am

honya96 wrote:
Jul 16 2018 2:03am
Lcd3 can show the temp with stock FW, I don't want to mess with the lcd FW..
Ah, I did't know that. It's Byte 9. So it is very simple to implement :-).

honya96 wrote:
Jul 15 2018 6:21am
Do you plan to show the temp on lcd3? I can order one for you if you will implement NTC10K, KTY 83, KTY 84 sensors.
I chose the TMP36 because it delivers an analog signal with no additional external hardware.
Perhaps we can use the pullup resistor (6,7K) on X4 for the voltage divider when using a thermistor? We will need 10bit ADC value to get satisfiying resolution?! Is a linear approximation OK? I would add two parameters to the Javatool for the calibration.

Code: Select all

Temperatur (°C) = a * ADC + b

So everybody can set the right value for his specific sensor... And I have to use a signed integer for the variable as the temperature can get negative...

regards
stancecoke

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Re: KT motor controllers -- Flexible OpenSource firmware for BMSBattery S/Kunteng KT motor controllers (0.25kW up to 5kW

Post by honya96 » Jul 16 2018 5:28pm

stancecoke wrote:
Jul 16 2018 2:17am
So everybody can set the right value for his specific sensor... And I have to use a signed integer for the variable as the temperature can get negative...
Great!!!

I can use KTY, they are used mostly in bigger motors, but NTC10K is the "most available" I would say, everyone has multiple of them at home without even knowing.

but it's not linear and not for high temps.

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Re: KT motor controllers -- Flexible OpenSource firmware for BMSBattery S/Kunteng KT motor controllers (0.25kW up to 5kW

Post by stancecoke » Jul 17 2018 3:19am

honya96 wrote:
Jul 16 2018 5:28pm
I can use KTY, they are used mostly in bigger motors,
I've derived the linear approximation coefficients for a KTY84-151 based on the mid values in the datasheet in the relevant temperature range, see picture.

a=1.6
b=-110.4

The calculation will need floating point operations in the code. I hope it will be fast enough.
The error of the linear approximation is acceptable, I think.

regards
stancecoke
calculation linear approximation coefficients KTY-151.PNG
calculation linear approximation coefficients KTY-151.PNG (93.87 KiB) Viewed 430 times
Last edited by stancecoke on Jul 18 2018 2:32pm, edited 1 time in total.

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Re: KT motor controllers -- Flexible OpenSource firmware for BMSBattery S/Kunteng KT motor controllers (0.25kW up to 5kW

Post by 1N4001 » Jul 17 2018 1:54pm

Where's the X4 pad? I can't find it on my PCB. Also, I would suggest using a 10k NTC. They're the most common type of sensor, are completely passive and used by just about every thermometer out there. Plus they're small and easy to integrate into a motor.

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Re: KT motor controllers -- Flexible OpenSource firmware for BMSBattery S/Kunteng KT motor controllers (0.25kW up to 5kW

Post by honya96 » Jul 17 2018 2:13pm

1N4001 wrote:
Jul 17 2018 1:54pm
Where's the X4 pad? I can't find it on my PCB. Also, I would suggest using a 10k NTC. They're the most common type of sensor, are completely passive and used by just about every thermometer out there. Plus they're small and easy to integrate into a motor.
But they are not that good for "in motor use" I think. You can get KTY cheap.. and if you buy motor with sensor allready, it's probably KTY.

@ stancecoke
As I understand It will show 130°C max?
Why not 150?

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Re: KT motor controllers -- Flexible OpenSource firmware for BMSBattery S/Kunteng KT motor controllers (0.25kW up to 5kW

Post by stancecoke » Jul 18 2018 2:20am

1N4001 wrote:
Jul 17 2018 1:54pm
Where's the X4 pad? I can't find it on my PCB.
This depends on your board revision. At my controller, you can find it somewhere below the yellow phase wire, see arrow.
Position of pad X4 on PCB.JPG
Position of pad X4 on PCB.JPG (72.48 KiB) Viewed 394 times
Image
1N4001 wrote:
Jul 17 2018 1:54pm
I would suggest using a 10k NTC.
The characteristic of a NTC is not linear at all, so we would need a third-degree polynomial for an acceptable calibration (takes much processor-time) or a look-up table (takes much memory)
calculation linear approximation coefficients NTC 10k.PNG
calculation linear approximation coefficients NTC 10k.PNG (108.15 KiB) Viewed 394 times

honya96 wrote:
Jul 17 2018 2:13pm
As I understand It will show 130°C max?
Why not 150?
a signed integer on an 8bitter can hold values from -127 to +127.

Code: Select all

B9: motor temperature, can be negative or positive,T(C)=(int8)B8+15,
    if temperature > 120C LCD screen is flashing.
    e.g 0xDA T=-23°C, 0x34 T=67°C
so the highest temperature that can be displayed on the LCD3 is 0x7F+15 = 127+15 = 142°C

I've added the temperature to the display protocol now. I've set the coefficients for a KTY84-151 in the config.h. I can't test it, as I have no LCD3 and no KTY84. The Java Tool is not updated with the new parameters yet, so please don't use it actually.

regards
stancecoke

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Re: KT motor controllers -- Flexible OpenSource firmware for BMSBattery S/Kunteng KT motor controllers (0.25kW up to 5kW

Post by fixvid » Jul 18 2018 4:49am

Hi all,

I would like to pair a kt controller with a yamaha pw drive. Would it be possible for the kt controller with/without open source fw to process the output of the Yamaha Torque Sensor?

There is no battery nor display so I would like to use a custom controller with raised voltage to overcome the low assist of Yamaha at higher cadence.

I made a new topic with this:
viewtopic.php?f=28&t=95306

Thx In advance

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Re: KT motor controllers -- Flexible OpenSource firmware for BMSBattery S/Kunteng KT motor controllers (0.25kW up to 5kW

Post by casainho » Jul 18 2018 4:54am

fixvid wrote:
Jul 18 2018 4:49am
I would like to pair a kt controller with a yamaha pw drive. Would it be possible for the kt controller with/without open source fw to process the output of the Yamaha Torque Sensor?

There is no battery nor display so I would like to use a custom controller with raised voltage to overcome the low assist of Yamaha at higher cadence.
You may have luck since I think Stancecoke have one of that motors and use(??) this firmware on it.
Developer of the Flexible OpenSource firmware for EBike motor controllers (TSDZ2 and KT) and LCDs (KT-LCD3 and Bafang 850C color LCD).

If you like my work, you can consider making a donation. I am being using the donations to buy needed resources for my developments. My paypal: casainho AT gmail.com.

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Re: KT motor controllers -- Flexible OpenSource firmware for BMSBattery S/Kunteng KT motor controllers (0.25kW up to 5kW

Post by -dg » Jul 18 2018 5:27am

casainho wrote:
Jul 15 2018 10:51pm
Sorry but I can't implement support for KT controllers on LCD3, because of time limitations. But I accept pull requests/contributions from others that want to make support for KT firmware.
Finally my controllers and dev boards arrived. I'm doing a little soldering practice before tackling the controllers and setting up the tool chain to be able to build. Meanwhile I've been studying up on the STM8 and skimming the code in the repo.

I suppose I'll find this out when I build it, but off hand, on the controller and on lcd3/5 how much of the flash and ram are in use? I have some feature ideas than might need more room, so I'm curious. Thanks.
If simplicity worked, the world would be overrun with insects.

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Re: KT motor controllers -- Flexible OpenSource firmware for BMSBattery S/Kunteng KT motor controllers (0.25kW up to 5kW

Post by stancecoke » Jul 18 2018 7:20am

casainho wrote:
Jul 18 2018 4:54am
fixvid wrote:
Jul 18 2018 4:49am
Would it be possible for the kt controller with/without open source fw to process the output of the Yamaha Torque Sensor?
You may have luck since I think Stancecoke have one of that motors and use(??) this firmware on it.
It was not me, but the user mtdr.
There are different generations of torquesensors in the yamaha drives. The older one delivers an linear output 0-5V, that's easy to implement. I don't know the one that mtdr showed, but it has 3 wires so perhaps it's an analogue output also. Perhaps you can check the voltage on the wires of the connector and post a photo of the sensor...

I never got a feedback from mtdr, if the open firmware worked for him finally...

regards
stancecoke

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Re: KT motor controllers -- Flexible OpenSource firmware for BMSBattery S/Kunteng KT motor controllers (0.25kW up to 5kW

Post by fixvid » Jul 18 2018 9:58am

stancecoke wrote:
Jul 18 2018 7:20am
casainho wrote:
Jul 18 2018 4:54am
fixvid wrote:
Jul 18 2018 4:49am
Would it be possible for the kt controller with/without open source fw to process the output of the Yamaha Torque Sensor?
You may have luck since I think Stancecoke have one of that motors and use(??) this firmware on it.
It was not me, but the user mtdr.
There are different generations of torquesensors in the yamaha drives. The older one delivers an linear output 0-5V, that's easy to implement. I don't know the one that mtdr showed, but it has 3 wires so perhaps it's an analogue output also. Perhaps you can check the voltage on the wires of the connector and post a photo of the sensor...

I never got a feedback from mtdr, if the open firmware worked for him finally...

regards
stancecoke
Thx, I somehow managed to understand German with Google translate.

From my understanding mtdr did make it work with s06 controller, but he didn't say a word about making it work with the Torque sensor.

Although I didn't buy the bike yet, the torque sensor has 3 wires. I'm somewhat hesitant to buy it if I cannot make to motor run efficiently.

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Re: KT motor controllers -- Flexible OpenSource firmware for BMSBattery S/Kunteng KT motor controllers (0.25kW up to 5kW

Post by stancecoke » Jul 18 2018 11:10am

I've now updated the Java Tool with the temperature coefficients. Would be nice, if somebody could test it with a LCD3!

regards
stancecoke

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Re: KT motor controllers -- Flexible OpenSource firmware for BMSBattery S/Kunteng KT motor controllers (0.25kW up to 5kW

Post by casainho » Jul 18 2018 11:16am

2 days ago I did the very first ride with our OpenSource firmware for TSDZ2, which is based on this KT firmware we did develop. That ride of 12kms went very well and because I was late for my Zumba class I hadn't time to be gentle with the motor and I always drove at max assist level/power!! To resume: we should be proud of our hard work!!

Also on LCD3, I implemented a new configuration submenu that just shows some data from the motor controller, like the raw ADC value of throttle and torque sensor, motor speed in ERPS, etc. And with this tests, I decided to remove from the firmware the automatic offset reading from the throttle and torque sensor, because for instance if a user connect a throttle after powering up the system, the motor start fast without any warning and that can be dangerous. Also, user can press that sensors at power up and the calibration will be incorrect and the system will not work well and user will not understand that bad behavior... -- my suggestion is for not using automatic offset reading for that sensors.

Developer of the Flexible OpenSource firmware for EBike motor controllers (TSDZ2 and KT) and LCDs (KT-LCD3 and Bafang 850C color LCD).

If you like my work, you can consider making a donation. I am being using the donations to buy needed resources for my developments. My paypal: casainho AT gmail.com.

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Re: KT motor controllers -- Flexible OpenSource firmware for BMSBattery S/Kunteng KT motor controllers (0.25kW up to 5kW

Post by honya96 » Jul 18 2018 1:52pm

stancecoke wrote:
Jul 18 2018 11:10am
I've now updated the Java Tool with the temperature coefficients. Would be nice, if somebody could test it with a LCD3!

regards
stancecoke
Can test it.

Do I need some pull up resistor as you wrote before? I think I removed it.

And then sensor between X4 and GND?

edit: Please add pause in the compiling again.

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Re: KT motor controllers -- Flexible OpenSource firmware for BMSBattery S/Kunteng KT motor controllers (0.25kW up to 5kW

Post by stancecoke » Jul 18 2018 2:41pm

honya96 wrote:
Jul 18 2018 1:52pm
Can test it.
Thanks! :D
honya96 wrote:
Jul 18 2018 1:52pm
Do I need some pull up resistor as you wrote before? I think I removed it.
Yes, it has to be 6.6kOhm for the derived calibration factors. You can take any other value e.g. 1k, just tell me, then I can derive the right values for Cal_A and Cal_B easily. It's just one cell in the excel sheet to be changed....
honya96 wrote:
Jul 18 2018 1:52pm
And then sensor between X4 and GND?
Yes, I emulated the KTY84 with a poti and it worked for the printout in diagnostics mode. You have to disable the diagnostics mode, otherwise the LCD3 will show nothing.
honya96 wrote:
Jul 18 2018 1:52pm
edit: Please add pause in the compiling again.
done :wink:

regards
stancecoke

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Re: KT motor controllers -- Flexible OpenSource firmware for BMSBattery S/Kunteng KT motor controllers (0.25kW up to 5kW

Post by honya96 » Jul 18 2018 3:03pm

few months old versions are working.. now I cant flash

>>> Filling PROGRAM MEMORY image in computer with Blank Value
<<< Filling PROGRAM MEMORY image in computer succeeds

>>> Loading file main.hex in PROGRAM MEMORY image in computer
(API) ERROR : No such file or directory

C:\BMSBattery_S_controllers_firmware-Master>pause
Press any key to continue . . .

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Re: KT motor controllers -- Flexible OpenSource firmware for BMSBattery S/Kunteng KT motor controllers (0.25kW up to 5kW

Post by stancecoke » Jul 18 2018 3:12pm

have you upgraded to SDCC 3.7.0, already? If not, please do, see tutorial...

regards
stancecoke

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Re: KT motor controllers -- Flexible OpenSource firmware for BMSBattery S/Kunteng KT motor controllers (0.25kW up to 5kW

Post by honya96 » Jul 18 2018 3:58pm

stancecoke wrote:
Jul 18 2018 3:12pm
have you upgraded to SDCC 3.7.0, already? If not, please do, see tutorial...

regards
stancecoke
Done, updated java also and waiting for stvd download link.. still not working
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Re: KT motor controllers -- Flexible OpenSource firmware for BMSBattery S/Kunteng KT motor controllers (0.25kW up to 5kW

Post by stancecoke » Jul 19 2018 1:51am

honya96 wrote:
Jul 18 2018 3:58pm
still not working
OK, there seem to be two problems in the path definition.

1. Please check, if the SDCC.exe (3.7.0) is located in this path

Code: Select all

C:\SDCC\usr\local\bin
If not, please adapt the first line of the Start_Compiling.bat according to your file system.

2. I've now changed the syntax "%~p0\" in the Start_Compiling.bat to "%~dp0" for the right syntax in the path to the cygwin binaries. The old syntax worked for me also, but now it's correct definitely.

I'll add the hint to check the path to the FAQs.

regards
stancecoke

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Re: KT motor controllers -- Flexible OpenSource firmware for BMSBattery S/Kunteng KT motor controllers (0.25kW up to 5kW

Post by geofft » Jul 19 2018 6:08am

stancecoke wrote:
Jul 19 2018 1:51am
honya96 wrote:
Jul 18 2018 3:58pm
still not working
OK, there seem to be two problems in the path definition.

1. Please check, if the SDCC.exe (3.7.0) is located in this path

Code: Select all

C:\SDCC\usr\local\bin
If not, please adapt the first line of the Start_Compiling.bat according to your file system.

2. I've now changed the syntax "%~p0\" in the Start_Compiling.bat to "%~dp0" for the right syntax in the path to the cygwin binaries. The old syntax worked for me also, but now it's correct definitely.

I'll add the hint to check the path to the FAQs.

regards
stancecoke
I've also tried to flash this branch, but seem to be having similar problems to honya96. My SDCC (running 3.7.0) file locations and paths all seem correct.

This is no immediate problem for me but I've attached my cmd dump for info, maybe you could take a look sometime... :)
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BBS02 V2 48v 750w, 12s lipo.
Q128H (36v 201rpm), KT36/48SVPR 20amp, LCD3, 48v 12s lipo.

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