Where to start in designing a USB hub?

[Seytonic]

Hi, I've made a few embedded projects recently built around arduino, though one of my projects requires a built in 2 port USB hub. I've searched around and can only really find schematics for controller chips that I could potentially use http://www.ti.com/lsds/ti/interface/usb-hub-controller-products.page?paramCriteria=no Though I'd like to understand what I'm doing rather than just following a schematic, if anyone could point me in the general direction of resources that could help me understand this topic a bit better that would be great.

[MosherIV]

one of my projects requires a built in 2 port USB hub. I've searched around and can only really find schematics for controller chips that I could potentially use

The reason you do not find any info on how to do it is because no body does it.
You just get a USB Hub device chip and implement the design around it.

Though I'd like to understand what I'm doing rather than just following a schematic, if anyone could point me in the general direction of resources that could help me understand this topic a bit better that would be great.

The classic book 'USB Complete' has the information that you need.
You could try a whole number of web sites :
http://www.usbmadesimple.co.uk/

But I have not checked them out.

in quick simple terms (from memory), a USB Hub must :
scan all the ports for insert/removal - tell the host when this happens
When insert detected, must provide power and do a handshake with the device to get type and power, then power device down again and report to Host. (I may be mistaken, it might be the host that requests the power up and handshake)
The host must then tell the hub what to do.
Why go to the bother when you can just get devices that do it all 

[Seytonic]

one of my projects requires a built in 2 port USB hub. I've searched around and can only really find schematics for controller chips that I could potentially use

The reason you do not find any info on how to do it is because no body does it.
You just get a USB Hub device chip and implement the design around it.

Though I'd like to understand what I'm doing rather than just following a schematic, if anyone could point me in the general direction of resources that could help me understand this topic a bit better that would be great.

The classic book 'USB Complete' has the information that you need.
You could try a whole number of web sites :
http://www.usbmadesimple.co.uk/

But I have not checked them out.

in quick simple terms (from memory), a USB Hub must :
scan all the ports for insert/removal - tell the host when this happens
When insert detected, must provide power and do a handshake with the device to get type and power, then power device down again and report to Host. (I may be mistaken, it might be the host that requests the power up and handshake)
The host must then tell the hub what to do.
Why go to the bother when you can just get devices that do it all 

Thanks for your response, though I probably wasn't clear enough, I'm not looking to implement it from the ground up I'm going to base it around a USB controller, its just I can't find any information other than the datasheets on how to go about it. Datasheets are great, but I've never really done anything like this before so if anyone has and has documented the process that's what I'm looking for.

[yngndrw]

I don't know if this is any use to you: https://www.tindie.com/products/mux/nanohub-tiny-usb-hub-for-hacking-projects/

The seller also has a 4-port version: https://www.tindie.com/products/mux/4-port-nanohub-tiny-usb-hub-for-hacking-projects/

[suicidaleggroll]

The controller's datasheet will tell you what it needs to work correctly.  What kind of additional information are you looking for?

[Seytonic]

I don't know if this is any use to you: https://www.tindie.com/products/mux/nanohub-tiny-usb-hub-for-hacking-projects/

The seller also has a 4-port version: https://www.tindie.com/products/mux/4-port-nanohub-tiny-usb-hub-for-hacking-projects/

Now this I like, after some searching I found the schematics  Perfect, thanks. The schematics for anyone who finds this thread in the future: http://muxtronics.nl/nanohub.html

[senso]

The TI chip and many others also have schematics, they even call it typical usage..

[amyk]

It depends what you mean exactly by "designing a USB hub". As others have mentioned, the ICs which are available require nothing more than power and a few passives. If you actually want to implement a hub, then you're going to have to read the USB spec.