Custom USB-C dock

[marq020]

Hi!

I'm not even sure if I'm in the right subforum, but let's try it anyway!
I'm looking into building a custom USB-C dock (for my Legion Y530). The idea is to just have a single cable doing video output (hdmi), audio (3.5mm) and a couple of USB-A (for mice and keyboards and what not).

The solutions I managed to find were either buying a dongle or building a "slide-in" dock which would plug ni whatever I want to the back of my laptop (that's simple enough, let's call that plan B).

I'm wondering if it's even possible to build what I want without special controllers for crap, just soldering connections from the USB C to at least an hdmi port and one USB A (not exactly sure about how pins in a C port work).

Pretty sure it's not how any of this works but figured I'd give it a shot.

Thanks!

[bob345]

Not possible with just soldering on connections. usb-c by far the most complicated usb standard out there and it can involve quite a bit of work even so get something like quick charge working right. A good example would be the raspberry pi 4 that pretty much botched their usb-c implementation.

[marq020]

Yeah I thought so, just thought I'd double check... slide in dock it is then!

Thanks!

[Hackentosher]

19 hours ago, bob345 said:

Not possible with just soldering on connections. usb-c by far the most complicated usb standard out there and it can involve quite a bit of work even so get something like quick charge working right. A good example would be the raspberry pi 4 that pretty much botched their usb-c implementation.

Absolutely. Usb c is ridiculously complicated, there are many different control ICs specifically for the port to help facilitate the dp, hdmi usb, audio, network, and other protocols. And that's just for data. The power configuration is also complicated, it takes up a hundred or so pages in the specification document. 

 

A note on the pi thing, it's not that huge of a mistake, they shorted the CC1 and CC2 pins together not realizing that they are read individually by the upstream device and are not mirrored like vbus or some other pins. For the most part, selecting the power request on your device is as simple as connecting the correct pull down resistors to CC1 and CC2, so theoretically all they need to do is respin the board with the fix applied. Hopefully that's not a huge hit to their production. 

[mariushm]

agree with everything above.... shame how usb evolved from something simple capable of 10 mbps and requiring only 2 data wires to a monstruosity of a standard with hundreds of pages of documentation.

 

[marq020]

53 minutes ago, tall_linus said:

Your laptop also has THunderbolt 3 ports. So going for a thunderbolt dock would be a better option. You can take a look at this selection of tb3 docking stations

Uh, how sure are you about that thunderbolt 3 support? The y530 doesn't have it, otherwise I'd be all up in it