10-24-2007 04:51 PM
10-25-2007 02:22 AM
10-25-2007 03:15 AM
10-25-2007 08:57 PM
08-12-2008 05:12 AM
In what way that can cause a problem ?
Actually i am using the same and get the same error.
But my design initially loads and i can launch XMD for once or twice then it says
Error:Unable to stop processor.
Check 1) .....
If so what would be the suggested Frequency?
08-17-2008 10:22 AM
If you're getting the "Unable to stop processor" error, then as I like to say "your processor has gone out to lunch".
This can happen
1) if the processor is getting bombarded w/ interrupts and there is no handler for it.
2) if the processor attempted a PLB read/write that was never ACK'd (and there is no handler for it). The parentheses are because this last problem has occured once or twice with a handler as well.
3) if the processor executed invalid instructions (I'm pretty sure there's an internal INT for this as well).
One way of performing a sanity check on the PPC405 is do to a 'rrd' from xmd after connecting. If all the registers come back with the same value, like all of them were smeared with it, its dead. The next step to the test is to try writing to a register and making sure that the value is correctly populated in the register. If this value is smeared to every register, like the previous problem, it's dead.
BTW, what is the bootcode for your PPC? You do know that unlike the MB, the PPC requires a block of RAM mapped to address 0xFFFFFFFC for the reset vector.
The PLB can run at 125MHz. The PPC can run at 125MHz. In fact I have designs w/ the PPC running at 300MHz. It appears the doc for the PLBv46 is missing the actual speeds in its corresponding table (table 14). From the PLBv34 and based upon the VII-Pro in -7 grade, a similar system to your (2 masters, and 4 slaves) could run at 169MHz, which is well above your requirement of 125MHz.
A rule of thumb is to have your PLB be a X:1 multiple of your PPC, so you have even clock divisions/requirements.