Small display for the Stark Varg MX

Stark71

Active member
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26
Location
Germany
Hi all,

I saw in multiple threads a discussion about an alternative for the mobile. I like to share my solution for this as I am also not a big fan on the MX for this. Also CEO said in an interview that they do not plan to develop any small display.

I connected my display between the VCU and the phone bracket. CAN is running surprisingly on 1MBaud instead of typically 500k. Anyhow, listening some messages and result was easy. Of course the wireless charging pad needs to stay at the bike. It works in parallel to the mobile as my display only listen.

For me important was:
1. SOC
2.Mode (1,2,3,4,5)

Additionally I found also Speed and status. For the status I receive values (neutral, active etc..) but I was not so interested.
I do not want to replace the mobile completely and I do not want to write to CAN.. just listening.

For the HW I took the ESP32. The display I tried 2-3 different version and finally took the LilyGo:

Housing is 3D printed designed by myself. Of course you need a small DC/DC (12V-->3.3V) converter and a CAN transceiver (I took the Sn655hvd230).

As a SW base I took it from Volos Projects:

Basically all the credits goes to him and his channel and in this specific case also ti nikthefix... Great guys!


actual_Display.jpeg

On the picture you can see SOC=26% in Mode 3 (my personal 50hp setting tuned in the mobile). My display is faster (a few ms) than the mobile because it is hard wired :)!

For the CAN bus. The important ID's are:

1. 0x303 --> Speed and Mode
// Serial.println("0x303");
Stark_Mode = frame.data[0];
Stark_Speed = frame.data[2] | (frame.data[3]<<8);
Stark_Speed = Stark_Speed / 10;
if(Stark_Speed>=200)Stark_Speed=200; //maybe in the future :) !!

2. 0x302 --> SoC
// Serial.println("0x302");
Stark_SoC = frame.data[6];
if(Stark_SoC>=100)Stark_SoC=99; //stay at two digits...

3. 0x407 --> Status
//Serial.println("0x407");
Stark_Armed = frame.data[4]; // 0x30(48) disarmed 0x38(56) armed 0x6(6) Relay open 0x10(16) relay closed

With this information it should be easy to use any CAN Display like M5Stack. I like the OLED and the screen ratio therefore I went the longer way


To make this clear. it has also some side effects. I do not receive any warning because I do not have the mobile with me while riding. (e.g. water pump error) luckily I (hopefully) had never some. As far as I see also the hour counter does not go up. Also no GPS states etc. are working... All for me not important. I have this setup roughly 1 year running without any trouble.. like my Stark MX

I do also have a Stark Varg EX but because I use it also on public road I do not plan to switch there. Maybe CAN data will be identically... I do not know.
Whatever you do, it is all on your own risk.

Happy to hear feedback.

BTW my first thread :) in this forum.

Thanks and regards
Christian
 

airmartl

New member
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1
Location
Austria
Is it possible to read these CAN information on the OBD connector or does the vehicle has 2 different CAN buses (OBD CAN and Vehicle CAN)
 

rs911

Active member
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37
Location
France
Very nice !

I think I will make one for myself too.
The main reasons are :
1. that it still can be used with the Stark phone compared to the iOS/Android app running on another phone because of the Bluetooth connection
2. I could convert the speed with the different transmission I'll use with my sumo setup
 

Theo

Well-known member
Likes
248
Location
Italy
Very nice !

I think I will make one for myself too.
The main reasons are :
1. that it still can be used with the Stark phone compared to the iOS/Android app running on another phone because of the Bluetooth connection
2. I could convert the speed with the different transmission I'll use with my sumo setup

Sorry to rain on your parade, but since you have recently written that you want to extend the warranty, are sure that you want to do this? @Stark71 warned us after all:

Whatever you do, it is all on your own risk.
 

rs911

Active member
Likes
37
Location
France
Sorry to rain on your parade, but since you have recently written that you want to extend the warranty, are sure that you want to do this? @Stark71 warned us after all:
It's readonly stuff, I'm not messing with something that would write on the VCU so no risk at all.
There are a ton of similar devices on automotive and just to name a few on VAG cars :
P3 gauge
CANchecked
FIS-Control
PolarFIS

It's basically like using a diagnostic tool on your car. You connect the tool to your car using an OBD2 port and then you can log data or clear DTCs.
None of that stuff will void the warranty 😉
 

Theo

Well-known member
Likes
248
Location
Italy
It's readonly stuff, I'm not messing with something that would write on the VCU so no risk at all.
There are a ton of similar devices on automotive and just to name a few on VAG cars :
P3 gauge
CANchecked
FIS-Control
PolarFIS

It's basically like using a diagnostic tool on your car. You connect the tool to your car using an OBD2 port and then you can log data or clear DTCs.
None of that stuff will void the warranty 😉

I know about the OBD2 ports for cars, but I'm pretty sure that the Varg MX doesn't have such a port and the bike in the pictures of the first post looks like an MX, that's why @AL_V has asked about the connectors, apparently. As far as I remember, there are no connectors available in the MX.
So, I would be surprised if for Stark Future it were ok to do this in an MX, even if it's for read only purposes and that's one of the reasons for which I haven't done it.

If your EX has some port for that purpose, than maybe it wouldn't void the warranty, but I would ask Stark anyways if I were in your shoes.
 

AL_V

Well-known member
Likes
289
Location
Canton, Ohio
I know about the OBD2 ports for cars, but I'm pretty sure that the Varg MX doesn't have such a port and the bike in the pictures of the first post looks like an MX, that's why @AL_V has asked about the connectors, apparently. As far as I remember, there are no connectors available in the MX.
I am guessing that he bought the same connectors that Stark used on the MX to connect the docking pad (However, I may be wrong, just a guess).
There is a guy on facebook selling a splice he makes for those connectors.
He has a male and a female with a pigtail coming off for lights or GPS or whatever small draw 12vdc.
So you plug it in between the bike and the docking pad.
 

Stark71

Active member
Likes
26
Location
Germany
Hi,

sorry, due to vacation I was offline.

To your questions.

1. Yes, display works parallel to the phone. (only read mode)
2. speed conversion due to transmission rate change is no problem at all. Calculation is inside ESP32.
3. temperatures. I did not check. Which temp is interesting? Motor? Battery? Information is sure available but to find it will be tricky...
4. Connector
- in the first step I made a Y-cable because I do not want to cut the original harness. Aliexpress is full of this connector: You have to take the 4 pin.


But connector Y-cable was too bulky. So finally I cut the wire of the wireless charging station direct after the connector and soldered +/- 12V and CAN H/L . In case of warranty I could buy a new one for 150€ and no one would realize any modification. I doubt that any ecu will detect an error due to additional reading. I did not find any OBD connector on the MX. But as I said, all at your own risk.

Regards
Christian

4pin_Stark.jpeg

CAN_Stark.jpeg
 

Stark71

Active member
Likes
26
Location
Germany
Hi airmarti,

I compared the data from the mobile directly with the CAN data on my computer by using free busmaster SW:


switching the modes and see what happened on CAN. meanwhile there are more advanced methods available but in my case (focus on Mode, Speed, SoC) it was very easy.

Just connect to the EX CAN and check the ID's from the first post. I see a high chance the MX is same like EX. Please share your result. Maybe we can reverse engineer the CAN.

regards
Christian
 
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