5510 EMIF - Can I use Asynchronous IF to connect to Synchronous Device ?

Hi All,

I have a USB device hooked off my 5510s EMIF, and can use it quite
happily using asynchronous mode on both DSP and USB device.

However, when the USB device runs in asynchronous mode it is not
capable of reaching the high USB2 bandwidth figures I require. To
achieve this, I need to run the DSP device in synchronous mode.

Initially I thought, no problem, I'll just run the 5510s EMIF in
synchronous mode. However it only offers SDRAM or SBSRAM as the
default device types, and I cannot think of a way of addressing my
USB devices registers using row/column addressing.

Then I thought, what if i run the EMIF as Asynchronous and the USB
device as Synchronous.

To do so, I have connected DSP CLKOUT to the CLKIN on the USB
device, and I'm running the CPU at 200MHz and CLKOUT/EMIF at 20MHz.

However, it looks like I have no control over when my SETUP, STROBE
and HOLD signals are asserted with respect to CLKOUT i.e. They can
be triggered at any CPU clock edge within the CLKOUT period.

Can anyone think of a good way to get around this problem ?

Thanks in advance for any repsonse.

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