Re: Carte Blanche

["Michael J. Mahon" <mjmahon@aol.com>]

Alex Freed wrote:
> Michael J. Mahon wrote:
> > Steve, it wasn't immediately apparent whether it was possible to
> > re-program the board while it is installed by running Apple II software.
> >
> > This would enable it to be a real "chameleon card", since configurations
> > could be loaded into the card in a few seconds to alter its personality.
>
> This ideas has been discussed on this forum but proved to be a huge 
> task. More on the software side than the hardware side. Porting the
> JTAG programming tool to an 8 bit CPU with rather limited resources
> is far from trivial. And if you absolutely have to have it, you
> probably can. It's not too hard to make a Wiggler-style interface 
> between an Apple parallel card and the JTAG port on Carte Blanche. Just 
> write the software :)

I'd be glad to write the software if it comes to that.

But I'd rather access the card through its bus connection than by
using another (parallel) card.  Since an Apple parallel card is
little more than an 8-bit latch, that doesn't seem difficult.

I presume that the data formats and protocols for JTAG programming
are straightforward...  I'd expect what is essentially a "copy file
to port" operation, with some handshaking, initialization, and cleanup.

-michael

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