From: Patrick Maupin on
On Mar 26, 7:58 am, Antti <antti.luk...(a)googlemail.com> wrote:
> well, USB 3.0 is the first one that needs NO PHY
>
> as the MGT's in some newer FPGA's are USB 3.0 capable directly
> just wire MGT to usb 3.0 superspeed pins, and that about it

I'm slightly confused by this statement. If 3.0 requires fallback
capability, how could FPGA hardware be compatible with 3.0 without
being compatible with an earlier version, and if FPGA hardware IS
compatible with an earlier version, how can you call 3.0 the first?
From: Andrew Jackson on
On 29/03/2010 06:00, Patrick Maupin wrote:
> On Mar 26, 7:58 am, Antti<antti.luk...(a)googlemail.com> wrote:
>> well, USB 3.0 is the first one that needs NO PHY
>>
>> as the MGT's in some newer FPGA's are USB 3.0 capable directly
>> just wire MGT to usb 3.0 superspeed pins, and that about it
>
> I'm slightly confused by this statement. If 3.0 requires fallback
> capability, how could FPGA hardware be compatible with 3.0 without
> being compatible with an earlier version, and if FPGA hardware IS
> compatible with an earlier version, how can you call 3.0 the first?

The compatibility arises because USB 3.0 uses a new connector that has
both USB 2.0 connections and the new (SuperSpeed) connections.

Andrew