I have had to admit defeat on my attempts to decode a DVB-ASI
signal using an FPGA. It was simply asking too much of the FPGA.
So I have decided to follow the suggestion in one of the comments
I received on this blog.
I have bought a DVB-ASI PCI card for $28 on eBay, it uses CY7B933
chips which have a synchronous output which appears compatible with
one of the modes of the Cypress USB chip we use on Express. That means
it should be a fairly easy job to remove the PCI interface chip and substitute
the FX2 fifo one instead. I will post more info when I get the 4 channel card.
In anticipation I bought a small quantity of FX2 boards from China
(the 56 pin ones).
I was thinking of making a small PCB for the project but as this will be a one
off project a nest of prototyping wire and my hot glue gun will be enough.
After all that is what boxes are for.