VOLVO+ Development Story (1)

The story went back to 2017, as I bought VOLVO XC60. The electronic tailgate can open with remote. But Volvo denied to close the tailgate remotely. In 2019 Chinese new year, I suddenly wanted to play it...

The record above is actually developing the mechanism called MITM, and you can read it to know more sight. I made some tools, tried to figure out the car's CAN bus protocol. Thanks to my friend lending his VOLVO XC70, let this "box" do experiment on the car, without worrying the car broken. Thank you again: we've figured out the CAN bus packet to close the tailgate





With the understanding to VOLVO car CAN bus, I can make the prototype. Including FW coding and HW design. I completed the first prototype in May of 2019. The PCB looks bad: a lot of flying wires and hot melt glue everywhere. Fortunately, it worked. There's only few components on the PCB, but I still had some hard time to make it work




The development board I used was named Blue Pill. It's cheap, easy to get, and strong: 72Mhz, 64K Flash, and 20K SRAM. The resource is quite sufficient in my design. I bought a lot the boards, and as developing, the boards burned piece by piece

CAN bus transceiver is the most painful spot. I bought 10x piece of TI SN65HVD230, which had the same voltage as CPU (3.3v). However, all of them were failure IC. Finally, I used NXP TJA1040 (5v) as temporal solution

The blue pill doesn't have 5v power source, so I bought some "adjustable" DC-to-DC buck to generate the 5v power. However, I probably adjusted the resistor in wrong direction. So the voltage changed widely (maybe 9v I guess). So the board burned again after capturing the video below

Anyway, let's see how the prototype working on my VOLVO car.


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