YT9218c 8227L Steering Wheel Controls and CANBUS hardware support

[pepelaalfa]

Hi my friends.
Im very interested on this subject.
I have a chinesse radio hizpo, and I want to make a canbus interface for my car.
I go inside the sofware on the radio using adb, and I find the apk who managed all the options for canbus. The apk is called MainUI, I decompiled it but i cant find the arrays, or list with the commands for every car brand.

My car is a PSA, and when a select PSA WC in the radio (code 148), the first 2 bytes or head code is 5AA5, if i select audi, the first is 2E, but with others is E6, and the code who start by 2E, (vol+) only works if the radio is in 2E mode. I havent any canbus decoder, so i can't monitorize the traffic, only I can read the serial port of the radio, and send to it commands.

I think the codes are inside a compiled library .so, i upload it in order to anyone try to decompile it.

https://srv-file6.gofile.io/download/tr2P6W/canjni.rar

 

[Audican]

Hello i can you help me i have head unit 8227l,My car is an audi a4 but it's not among the models that are written in the canbus protocol. Can i update can bus protocol?
I buy can bus decoder for audi a4..
But in head unit nit chenge nothing...

 

[sergiotacchini]

problema autoradio tesla style per buick ,opel,cruze...

ho un problema con autoradio per opel,buick..... modello tesla :

Android: SD8227_HW:1.0_SW:0.3.4_20180917
system: 4.4.2 kenel: 3.4.35
cpu: ARMv7 Processor rev 3 (v7l) X 4
display: 768*1024(6bits)
CAN: BNR-Focusexcelle(H)-V12.0-Connected
MCU1: HW8227-0.1-SW0-6.6
CanVersion info: BINARY BK V209
ha queste caratteristiche ma dopo un aggiornamento alla versione 6.0 non ci sono piu' i comandi al volante,qualcuno puo' aiutarmi?:

 

[Mohie.soheim]

Sorry, can't seem to find the relevant Git. Do you have any more info on that?

Here is what I've found so far;

Action			DEC				HEX
Vol+			46 32 2 1 1 219			2E 20 02 01 01 DB
Vol-			46 32 2 2 1 218			2E 20 02 02 01 DA
Next			46 32 2 3 1 217			2E 20 02 03 01 D9
Back			46 32 2 4 1 216			2E 20 02 04 01 D8
BT connect		46 32 2 5 1 215			2E 20 02 05 01 D7
Mute/Unmute		46 32 2 6 1 214			2E 20 02 06 01 D6
Home/Switch app		46 32 2 7 1 213			2E 20 02 07 01 D5
		

Front left door		46 65 2 1 1 186			2E 41 02 01 01 BA
Front right door	46 65 2 1 2 185			2E 41 02 01 02 B9
Rear left door		46 65 2 1 4 183			2E 41 02 01 04 B7
Rear right door		46 65 2 1 8 179			2E 41 02 01 08 B3
Trunk			46 65 2 1 16 171		2E 41 02 01 10 AB
Parking brake		46 65 2 1 32 155		2E 41 02 01 20 9B
Wiper fluid level	46 65 2 1 64 123		2E 41 02 01 40 7B
Seat belt		46 65 2 1 128 59		2E 41 02 01 80 3B
		
Closes decoder soft?	46 34 1 0 0 220			2E 22 01 00 00 DC

Still trying to decode the messages from the head unit so I can send the messages to the OEM LCD in the car. Missing phone buttons, play/pause, mode....
Would be great to find other commands but even when dumping prepared hex filed this is very slow... :silly:

Hello sir,
Please how can i enter this codes in the canbus setting

 

[morcibacsi]

Hi, I was doing some research on a Junsun head unit. It is "specially crafted" for Peugeot 307 cars, but as I was digging through various forums on the internet it seems it is the same MTK 8227l based Android unit as the others. It comes with a Raise CAN bus adapter which translates the CAN signals to the unit to serial ttl signals on 19200 baud with 8 databits and 1 stopbit no parity. Some CAN bus messages are translated to this ttl signal, howerver some of them a controlled in an analogue way. For example the box detects the reverse gear on the CAN bus but it uses a wire to signal the head unit to show the picture of the camera the same goes for the display dimming and also for the power-on signal. I have created a small Arduino library for the button presses and the trip computer information. As I mentioned the box is for a Peugeot, so if you want to use my lib, you have to select that one from the settings.

The arduino library: https://github.com/morcibacsi/JunsunPSARemote

The button codes:

  Source                 0xFD 0x04 0x02 0x11 0x17   
  Seek up                0xFD 0x04 0x02 0x12 0x18   
  Seek down              0xFD 0x04 0x02 0x13 0x19   
  Vol up                 0xFD 0x04 0x02 0x14 0x1A   
  Vol down               0xFD 0x04 0x02 0x15 0x1B   
  Mute/Unmute            0xFD 0x04 0x02 0x16 0x1C   
  Scroll up              0xFD 0x04 0x02 0x17 0x1D   
  Scroll down            0xFD 0x04 0x02 0x18 0x1E

I attached some screenshots from the device. And photos of the CAN adapter. It has a TJA1055 CAN transceiver and an ARM based microcontroller called Pocket Link (maybe an STM32 knock-off ?)

Unit description:
HMI: JC.D.Q.F.2.01.2020.07.13.09.30
MCU: TS907.190518(H)
MEDIA: HC_v2.0.0.200416_0930(v1.71)

 

[YosCoh1234]

Question about common ground

morcibacsi - I am trying to use your library, currently without success. I had a question regarding your commend about connecting a common ground. I have my Arduino powered via usb from the car multimedia, is this considered common ground? I measured the difference in voltage from the ground entering the multimedia and the arduino pin and it had 0.4v.
If this isnt a good solution shat should i do? Connect the arduino ground pin to the ground on connector c? Something else?

I am new to electronics so not that familiar with the concept of common grounds.

Thanks

 

[morcibacsi]

Common GND means that you need to connect one of the GND pins on the ESP32 to the GND of the head unit. You need to find that. It should be the same as the GND of your car. In a fakra (quadlock) connector it is pin number A16 on an ISO A connector it is pin number 8.

 

[YosCoh1234]

Found more info

While looking into this found more info that may be of interest in this thread:
See: https://github.com/runmousefly/Work/blob/master/MctCoreServices/src/com/mct/carmodels/RZC_PeugeotSeriesProtocol.java
This contains more id's that should work.
Credit to: https://forum.xda-developers.com/android-auto/mtcb-android-head-units-qa/canbox-decoder-reverse-engineering-t4057759/page2