There are some pieces missing from video.  Michael's clock_gen.v
appears to be to spec, although I haven't tested it properly.

One problem is that its output is wired directly into the video logic.
 In fact, the output from that should be the 4X video clock, and then
we need additional logic to divide it down.  Moreover, that divide
logic must not simply divide the clocks.  When dividing a 2X clock by
2, we need two output signals; one is the 1X clock (through a BUFG),
and the other is a register in the 2X clock domain that indicates the
phase of the 1X clock (basically, just mirroring it).  There is an
analogous thing for a 4X clock, where the phase bus is four 1-hots.  I
can provide the proper dividers, but I'm going to need help wiring it
in.

Secondly, there is no logic in there that actually connects the video
controllers to the pins.  The two heads are different, so that logic
needs to go at the top level.  I can provide that too, but again, I
need help wiring it in.

Thanks.

-- 
Timothy Normand Miller
http://www.cse.ohio-state.edu/~millerti
Open Graphics Project
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