Forums

SAM-BA related issue on AT91SAM9G20

Started by Vikas Sharma May 15, 2010
Hello
i am using AT91SAM9G20 CU-B rev MCU and SAM-BA 2.8V.

I Open the SAM-BA , with SAM-ICE JTAG connected between Host PC and the
board. and burn the bootstrap and the u-boot image.
Now the board is up with the u-boot. If i want to reburn the images on the

nand , i could not open the SAM-BA, SAM-BA gives
"NO valid Processor ID found" error message.
It means on empty NAND based MCU board is only able to connect with JTAG.
But functionality of SAM-ICE, is to burn the new image, even it is having
images.
for making SMA-ICE work, i have to erase first block of NAND. But what
happen if Board is having only bootstrap not Uboot.
We didnt give any Jumper settings for Nand flash enable or disable.

Can some one know, how to solve this problem. Or advanced version of
SAM-BA can solve it ??

Thanks and Regards
Vikash Sharma
Software Engineer
On Sat, 15 May 2010 15:08:40 +0530
Vikas Sharma wrote:
> Can some one know, how to solve this problem. Or advanced version of
> SAM-BA can solve it ??

SAM-BA connects to the initial boot code that runs as internal to the
AST91SAM9G20 device. If that boot code finds nothing to boot on
startup, it waits around for a SAM-BA connection, otherwise it starts
that boot.

So the only way to make sure that SAM-BA can connect to a device is to
erase the memory that it could boot from, or to open jumpers so that
during the early boot phase (until you can connect with SAM-BA) the
9G20 can't find that external memory, and then reconnect the
memory/jumper once you get the "ROM Boot>" prompt on the serial port
(which should be nearly instantaneous).

Dan
2010/5/15 Vikas Sharma

>
> Hello
> i am using AT91SAM9G20 CU-B rev MCU and SAM-BA 2.8V.
>
> I Open the SAM-BA , with SAM-ICE JTAG connected between Host PC and the
> board. and burn the bootstrap and the u-boot image.
> Now the board is up with the u-boot. If i want to reburn the images on the
> nand , i could not open the SAM-BA, SAM-BA gives
> "NO valid Processor ID found" error message.
> It means on empty NAND based MCU board is only able to connect with JTAG.
> But functionality of SAM-ICE, is to burn the new image, even it is having
> images.
> for making SMA-ICE work, i have to erase first block of NAND. But what
> happen if Board is having only bootstrap not Uboot.
> We didnt give any Jumper settings for Nand flash enable or disable.
>
> Can some one know, how to solve this problem. Or advanced version of SAM-BAcan solve it ??
> Thanks and Regards
> Vikash Sharma
> Software Engineer
>
I had a similar problem with a at91sam9260 processor on a custom board.
I dont know the availiable boot strategies of the 9G20 processor, but on the
9260 there is a BMS (Boot Mode Select) pin.
If you close the pin and do a reset the 9260 cpu will not to boot from NAND.

That way i was able to reflash with samba.

*hth*

ortwin
On Mon, 17 May 2010 09:16:27 +0530
Vikas Sharma wrote:
> Ok thanks for your reply. That is correct nand flash has greater
> priority than SAM-BA boot. But Samba is a Jtag used to dump the Code,
> even if, board is having correct code.

I haven't used the G20, so I'm not sure, but my experience on the 9261
was that I could get the processor into states where my could would, on
startup, quickly get the device into a state where I couldn't get the
SAM-ICE device to interrupt it and reprogram it, and having a
consistent way to get into the ROM Boot prompt was the only way I could
talk to the device again.

Maybe someone else here knows more?

Dan
Hi,

Ok thanks for your reply. That is correct nand flash has greater priority
than SAM-BA boot. But Samba is a Jtag used to dump the Code, even if,
board is having correct code.
Otherwise there is no difference between USB-slave and SAM-ICE jtag
debugger.
As i also worked with AT91SAM9260 MCU board (It's architecture and working
is almost same except working frequency).
There JTAG can able to re-dump the new code.

My problem is that, we didnt provide jumper settings to disable NAND
flash. If Nand flash is having bad code in first sector, then we are not
able to dump correct code in NAND flash.

Hi Ortwin Angermeier,
I never face this problem on AT91SAM9260 processor.

Thanks and Regards
Vikash Sharma
Software Engineer

Dan Lyke
Sent by: A...
05/15/2010 09:24 PM
Please respond to
A...
To
A...
cc

Subject
Re: [AT91SAM] SAM-BA related issue on AT91SAM9G20

On Sat, 15 May 2010 15:08:40 +0530
Vikas Sharma wrote:
> Can some one know, how to solve this problem. Or advanced version of
> SAM-BA can solve it ??

SAM-BA connects to the initial boot code that runs as internal to the
AST91SAM9G20 device. If that boot code finds nothing to boot on
startup, it waits around for a SAM-BA connection, otherwise it starts
that boot.

So the only way to make sure that SAM-BA can connect to a device is to
erase the memory that it could boot from, or to open jumpers so that
during the early boot phase (until you can connect with SAM-BA) the
9G20 can't find that external memory, and then reconnect the
memory/jumper once you get the "ROM Boot>" prompt on the serial port
(which should be nearly instantaneous).

Dan
Hello
i am using AT91SAM9G20 CU-B rev MCU and SAM-BA 2.8V.

I Open the SAM-BA , with SAM-ICE JTAG connected between Host PC and the
board. and burn the bootstrap and the u-boot image.
Now the board is up with the u-boot. If i want to reburn the images on the

nand , i could not open the SAM-BA, SAM-BA gives
"NO valid Processor ID found" error message.
It means on empty NAND based MCU board is only able to connect with JTAG.
But functionality of SAM-ICE, is to burn the new image, even it is having
images.
for making SMA-ICE work, i have to erase first block of NAND. But what
happen if Board is having only bootstrap not Uboot.
We didnt give any Jumper settings for Nand flash enable or disable.

Can some one know, how to solve this problem. Or advanced version of
SAM-BA can solve it ??

Thanks and Regards
Vikash Sharma
Software Engineer
I had a similar problem with a at91sam9260 processor on a custom board.
I dont know the availiable boot strategies of the 9G20 processor, but on
the 9260 there is a BMS (Boot Mode Select) pin.
If you close the pin and do a reset the 9260 cpu will not to boot from
NAND.

That way i was able to reflash with samba.

*hth*

ortwin