[rescue] Re: Happy happy happy! Joy joy joy!

Joshua D. Boyd jdboyd at celestrion.celestrion.net
Tue Jun 3 15:48:51 CDT 2003


On Mon, Jun 02, 2003 at 03:22:48PM -0700, Skeezics Boondoggle wrote:
> On Mon, 2 Jun 2003, Joshua D. Boyd wrote:
> 
> > On Mon, Jun 02, 2003 at 07:50:31AM -0700, Skeezics Boondoggle wrote:
> > 
> > > Virtual Console [0] (borrowing? the JTAG support from the SC2000,
> > > actually), created the first "system domains" in a Unix box (fairly
> > 
> > Is that any relationship to the JTAG stuff I'm doing?
> 
> I dunno, what kind of JTAG stuff are you doing? :-)  

I'm using it to program flash chips.

> I'm talking about the
> SPARCcenter 2000, not the LSI SC2000 (which pops up in Google as a popular
> JTAG prototyping/debugging tool), in case there was any confusion...

And I was refering to the SC2k and CS6.4k machines, not that LSI SC2k.
 
> I haven't found any on-line copies of the hardcopy docs I have, but
> haven't searched very hard yet.  The big difference between the JTAG
> implementations is that the CS6400 requires that the cable be hooked up to
> the SSP for normal functioning; if the SC2000/E control board detects that
> the JTAG interface is connected, it drops all the CPUs into slave mode and
> halts very early in POST - so on that machine it's only useful for factory
> burn-in and diagnostics.  But they mention that you could, in theory, use
> the JTAG port to monitor and detect hardware faults without disturbing the
> running OS, but that was never implemented.

Are you aware that there is a JTAG IEEE standard, and I'm begining to
suspect that Sun's JTAG is just that, except with undocumented
registers (which are left to the implementor anyway).



More information about the rescue mailing list