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Comment by zanny | Hacker News Reader

Having never tried to program a thunderbolt bus driver, but knowing that writing USB packet control code as being the biggest pain in the ass because the entire standard is a hodge podge mess, I wonder if Thunderbolt is easy to implement connectors for.

Really though, the problem is like most licensed Intel tech they charge out the ass for licenses. They heavily jack up Intel CPUs and Thunderbolt to subsidize their huge R&D budget.

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Greg Kroah Hartman wrote about implementing Thunderbolt for Linux: http://www.kroah.com/log/linux/hardware.html (not a pretty story)

I suspect Intel has realised that people who need Thunderbolt have no practical alternative. May as well charge what that market will bear for a while.

AMD does have a low cost alternative - Lightening Bolt http://en.wikipedia.org/wiki/Lightning_Bolt_(interface) - and I will admit that if it takes off and beats Intel/Thunderbolt I will smile a bit. It will be AMD64 all over again.

I'm curious as to how the hell Intel can charge huge license fees on a pci express passthrough port. Though, it doesn't sound like Lightning Bolt is similar - the Displayport part, maybe, but USB is serial and has high latency compared to the pcie bridge.

> I'm curious as to how the hell Intel can charge huge license fees on a pci express passthrough port.

They aren't - they charge the fees for Thunderbolt. You can't claim something supports Thunderbolt without paying licensing fees.

> it doesn't sound like Lightning Bolt is similar

You can draw a venn diagram and find that all three have an overlap. A desire for fewer cables, to be able to connect lots of stuff, and bang for the buck. Display, storage, peripherals etc. Outside of the venn diagram, Thunderbolt does have low latency, but most don't need or want to pay for it. If Thunderbolt support was as pervasive and cheap as USB, it would be a different conversation.

How do you consider the USB standard a mess? I am quite impressed with it as a low-cost peripheral port that requires minimal hardware resources. I agree, it can be a pain to write for. My biggest difficulty was crafting HID descriptors! Yikes!

Have you ever tried to push more than 6 keys on your keyboard? e.g. in local two-player games.

Modern gaming motherboards come with a PS/2 port for a reason...

Modern gaming keyboards come w/ full n-key rollover over USB. My Noppoo Choc Mini is capable of full NKRO whereas my Model M can't do the same over PS/2.

USB doesn't impose a simultaneous key press limit that low, the keyboard does. The 'Report count' field of the 'Key codes' usage page of the keyboard's USB endpoint descriptor determines the maximum number of simultaneous key presses. This field is a byte, so it could be up to 255.

The keyboard endpoint example in the USB HID spec does have 'Report count' set to 6.

Thunderbolt is just a long distance version of PCI Express, so existing PCIe device drivers should work just fine.

This sounds very interesting. I guess the only reason there has been no adoption of thunderbolt is just the silly license rent seeking Intel tries to pull on the interface, a lot like firewire.

Licensing fees have nothing to do with it. The reason is that Thunderbolt is expensive to manufacture, and mass-market computers have tiny profit margins.

Adoption is starting. Newegg lists a variety of Thunderbolt gadgets. Mostly it seems to be storage products, where 10 Gbps Ethernet is needed but makes Thunderbolt look cheap.

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