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Search - "ლ(ಠ益ಠლ)"
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Boss sends e-mail telling everyone we have funding for 1+ year.
Two weeks later 50% of employees laid off.
ლ(ಠ益ಠლ)10 -
FFUUUuucccckkk me sideways. So I decided to look into USB type-c's power delivery and alt modes. Cause I kinda want to make an adapter card to run my displays over a single cable. TLDR of the rest: USB-C has some huge capabilities which noone is interested in using since its way to complex to handle for what its worth in the end.
Now PD alone is kinda ok to deal with since a lot of powerbanks use it and some hobby guys documented how to work with it. I find it really odd thou that you NEED to use a dedicated IC for using the configuration chanel to negotiate how much power you can draw. Why the USB standard didnt use some simple 5V low speed signalling? Also the standard says that you only have to implement 5v 0.6A with every other power level being optional. (This is also true for cables. Most manufacturers use only the USB 2.0 standard for them and brag about how fast type-C is. ლ(ಠ益ಠლ) )
Now to the alt modes. These motherfuckers are a real shitshow to deal with. First you need a Mux to deal with USB-C's two way insertion, so your signals wont get flipped. Next thing is that you have four lanes at your disposal in alt mode. Which you can either use for four Display Port Lanes or two DP lanes and two USB 3.0 lanes. (You always get USB 2.0) Now you may think that there would be one simple chip to do it all? Nope you need atleast two at the price of 6$ each. One for PD and one for Alt modes. Both are very hard to solder (QFN, 0.5 mm pitch 40+ pins) TI ended up being the only one with a decent offering of IC's that do what I need. As for working with them, you would think that you just slap a simple MCU on there that communicates over I2C or SPI to configure the chips? Nope! You program the chips memory from which it configures itsself. And the programming is done with some TI tool which gives me no idea as to how you can handle everything whith no control logic behind it.
Looking into alternative IC's leaves me with cypress semi. And their documentation is basically a total mess. I wanna know what that chip is good for and what I need to do to make it work. I dont care about technical details mixed with marketing jargon nobody understands. And I really despise that I have to register just to download a datasheet. Especially since there is no info about it on the main page.
And this whole rant hasnt even touched the topic that USB-C only uses DP and nothing else. So you better hope that you have DP++ so you can use a passive conversion.
This was my Ted Talk about USB-C. Some info in it may be subject to my stupidity and errors as it currently is 02:15 in the morning and I need some sleep.14 -
My client might just make our designer ragequit. 30 days ago he said: ohh this login page looks empty, I want images in the background. 15 days ago he said: I like the images, but change this part and this part. Today he said: I don't like any of the imagea, get rid of them. ლ(ಠ益ಠლ)3