So I've done a little more scope probing, and I can see a TCK out of the
FT2232, but not on the TCK pin, so that backs that up.  I'll take a closer
look at the schematics and try to find out what drives that.

On Thu, Dec 17, 2009 at 10:35 PM, David Brownell <davi...@pacbell.net>wrote:

> On Thursday 17 December 2009, Charles Vaughn wrote:
> > revision notes mention SWO support being added, which uses TDO and TMS.
>
> Your problem signal is TDO (that's giving "all ones" output), so
> this looks like the right track...
>
> Looks to me like the way they added SWO support involved adding
> an additional control signal, which the previous revision didn't
> use.  And thus, the previous OpenOCD driver didn't use... so one
> theory is that said signal is driven wrong, disabling JTAG.
>
> In the best of worlds, they used the same signal as various other
> boards, so you could just switch to the other interface config
> (which doesn't advertise itself as being for the '811 board).
> ISTR those go through CPLDs ... this one seems not to do that,
> I mis-remembered.
>
> Less optimally you'd have to tweak src/jtag/driver/ft2232.c to
> understand this as yet another variant.
>
> - Dave
>
>
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