FPGA Central

I want to be able to read files off the compact flash card through the
xilinx system ace chip which is connected to a xilinx virtex 2e FPGA.
The compact flash card is formated as FAT12. Has anyone done this
before, or at least could point me in the right direction in
implementing this in verilog?

Thanks,

frank

Hi,

Most likely, you will need to interface to the SystemACE MPU
port (as a "memory mapped peripheral") and then implement a
FAT12 or FAT16 filesystem reader to access the file of interest...

If you are using EDK to build a PowerPC/MicroBlaze system,
you can make use of a peripheral in EDK, the OPB to SystemACE
bridge, for the hardware portion of the interface. There is
also an XilFatFS library that helps with the FAT filesystem.

If you are building a custom design not using EDK, you'll need
to implement something similar. Maybe you could do it with
PicoBlaze and a small program you write... But you'll need
to know about FAT filesystem to get it right.

Another option to simplify things is to use some clever format
of the card to have a FAT partition followed by another unused
partition. I think you could then put your data in specific
sectors in the unused partition and have a FSM or other simple
processor pull the data off the disk from known sectors using
the MPU interface. This removes the need to implement a FAT
file system. But now you have to write some utilities to get
your data into specific sectors of the disk...

There's also a design on opencores.org which is relevant but
I don't know how you'd directly use it with SystemACE CF.

Eric

Frank Wang wrote:
>
> I want to be able to read files off the compact flash card through the
> xilinx system ace chip which is connected to a xilinx virtex 2e FPGA.
> The compact flash card is formated as FAT12. Has anyone done this
> before, or at least could point me in the right direction in
> implementing this in verilog?
>
> Thanks,
>
> frank

Frank Wang <ftwang@nospam.berkeley.edu> wrote in message news:<clpmhi$2sf1$1@geode.berkeley.edu>...
> I want to be able to read files off the compact flash card through the
> xilinx system ace chip which is connected to a xilinx virtex 2e FPGA.
> The compact flash card is formated as FAT12. Has anyone done this
> before, or at least could point me in the right direction in
> implementing this in verilog?
>
> Thanks,
>
> frank


Which os/sw environment or are you trying this in pure verilog?

If linux-ppc, it is very easy. Xilinx did it for you already.

Search xilinx's website for info.

-Tony

T Lee wrote:
> Frank Wang <ftwang@nospam.berkeley.edu> wrote in message news:<clpmhi$2sf1$1@geode.berkeley.edu>...
>
>>I want to be able to read files off the compact flash card through the
>>xilinx system ace chip which is connected to a xilinx virtex 2e FPGA.
>>The compact flash card is formated as FAT12. Has anyone done this
>>before, or at least could point me in the right direction in
>>implementing this in verilog?

>
> Which os/sw environment or are you trying this in pure verilog?
>
> If linux-ppc, it is very easy. Xilinx did it for you already.

Similarly, Microblaze uClinux also supports the sysace driver. You can
mount any filesystem you like on the CF card, FAT included.

Cheers,

John

Hello,

I too want to be able to do this too--but I want to do it before the
vxWorks OS is up--actually, I want to use this capability to copy a
vxWorks image off of the CF into RAM and then jump to the RAM image. I
am not certain of the CF formatting--I want to use it just like Xilinx
provides on the ML310 development board.

I've not been able to find any Xilinx driver/info that supports file IO
at the Xilinx level. I saw some earlier posts of persons trying to use
FILE* and standard file IO things--but I haven't found anything that
indicates this level of file IO is supported. Can anyone clarify or if
you've done something similar, share?

Thanx,

Paul