In article <608b6569.0411130932.280e759f@posting.google.com> larwe@larwe.com (Lewin A.R.W. Edwards) wrote:
>
>Ah, Saturday. Time to sit down and play with this PowerPC board. I
>installed a series resistor so the COP port on the board is supplying
>IO power (3.3V) and fired everything up. But Commander gives me the
>dreaded 03; cable disconnected error. If I query registers, I get
>either all 0s or all 1s (randomly, it seems).
>
>The only thing I can do is reset - that DOES work, so I know the
>interface is basically supplying the right signals.

Why I give you ask if you know the interface is basically supplying
the right signals?

>There is a jumper on the Wiggler board with RD and WR positions; I've
>tried shorting both and neither way makes a difference.

Women like to wear their hair longer and men have it much shorter.
Both sexes shave it all off when they're in active military service.

>There is

What on earth are you talking about?

--
Lady Chatterly

"So KK (he is almost smart enough to get his 3rd K) tell everyone what
you really think of Lady Chatterly..." -- Aratzio

Hi Allan,

> Try dropping the speed of the wriggler way down. The range is 1 to 8.
> if you try 8 go get a cup of coffee between commands.  If reset works I 

Hey, thanks - that suggestion was on the money. I find that at a setting
of 5 I can read registers and flash but not RAM. Strange, I wonder if
this means that SDRAM refresh is stopped while the BDM interface is
working (that sounds pretty screwed up if it's true).

I didn't install a resistor pack on the empty space yet, mainly because
I don't know what values ought to go there (and a secondary issue being
that I don't have any 0603 packs - I'll have to find a board to scrounge
it off). Maybe that will improve my results.

larwe@larwe.com (Lewin A.R.W. Edwards) wrote in 
news:608b6569.0411130932.280e759f@posting.google.com:

> Ah, Saturday. Time to sit down and play with this PowerPC board. I
> installed a series resistor so the COP port on the board is supplying
> IO power (3.3V) and fired everything up. But Commander gives me the
> dreaded 03; cable disconnected error. If I query registers, I get
> either all 0s or all 1s (randomly, it seems).
> 
> The only thing I can do is reset - that DOES work, so I know the
> interface is basically supplying the right signals.
> 
> There is a jumper on the Wiggler board with RD and WR positions; I've
> tried shorting both and neither way makes a difference.
> 
> There is also space on the target board for pullup resistors on four
> of the COP port pins; are these required?
> 

Try dropping the speed of the wriggler way down. The range is 1 to 8.
if you try 8 go get a cup of coffee between commands.  If reset works I 
am told the JTAG/COP is working.  I have seen the same type of problems 
on my 8260.  The answer was to drop the speed untill I could read / write 
to memory reliably.  My speed ended up being 4.


Allan

Ah, Saturday. Time to sit down and play with this PowerPC board. I
installed a series resistor so the COP port on the board is supplying
IO power (3.3V) and fired everything up. But Commander gives me the
dreaded 03; cable disconnected error. If I query registers, I get
either all 0s or all 1s (randomly, it seems).

The only thing I can do is reset - that DOES work, so I know the
interface is basically supplying the right signals.

There is a jumper on the Wiggler board with RD and WR positions; I've
tried shorting both and neither way makes a difference.

There is also space on the target board for pullup resistors on four
of the COP port pins; are these required?