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Re: SimmStick FPGA module
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keep
components
different
Java program.
serial interface.
during
you are
want to
configuration
for the Flash
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complicate

 Yes. Indeed at my company we have a design that uses an FTDI FT2232C
USB controller to:

 1- Power the board (up to 500mA@5V but you can also use external
power).
 2- Implement a JTAG interface.
 3- Implement a serial/FIFO communication line.

 You get all these from a single cable and that is very useful for
development. The FT2232C (http://www.ftdichip.com/Products/FT2232C.htm )
implements two versatile IO ports and supports a smart bit-bang mode
(MPSSE), so you can do serial or FIFO communications with one channel
and JTAG programming or debugging with the other in parallel (you even
get some GPIOs that are very handy if you need to configure your board
on the fly). We use those 'mini' type-B USB connector that save a lot
of space, and you can buy the cables cheap from Palm or mobile phone
accessory suppliers.

 Since you are fond of Java, you might enjoy the Java bindings for the
FTDI direct driver at http://jd2xx.dev.java.net/ which I maintain. I
have personally implemented an MPSSE JTAG controller using it (tested
with Xilinx FPGAs), it is not very difficult.

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modules,
larger modules.

 I guess the DIMM-PC is as standard as it gets
(http://www.jumptec.de/product/we_docs/dimm.php ). Every vendor seems
akin to implement their own standard; besides the world is mostly going
high-speed serial now... If you want your own parallel edgeboard
connector there are those universal 132-pin AGP connectors that sell
for less than a dollar in small quantities... just an idea.

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fun to discuss several
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 Ain't that GREAT (TM)? At least if you finally mess up you can blame
or share the guilt with others :)

 Luck with you project.

--
PabloBleyerKocik /
 pbleyer        / "Their primitive minds couldn't accept the truths."
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Re: SimmStick FPGA module
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components
different

The AT76C712/3 is a small AVR CPU with USB that boots from a
(AT45DBxxx) serial (SPI) dataflash memory
The dataflash can also contain the configuration data.

If you let the device run the USB Mass Storage Adapter device class
then the programming can be as simple as a drag and drop
to the file system.   You can probably setup your
development environment to save the bitstream to the new "USB key"
The onboard AVR runs 48 MHz so your configuration should be quite fast.

Typically dataflash is much cheaper than configuration memories
and you can get them in sizes up to 64 Mbit today.
In SO-8 pinout, they are up to 16 Mbit today, but the 128 Mbit in SO-8
is around the corner.

During configuration, the AVR can read a script file from
teh FAT file system and can react accordingly
maybe also taking some DIP switches in account.
(You could have several configurations, very easily)

After configuration, the AVR could switch to a USB<->Serial adapter.
(Disabling the USB Mass Storage, until a key is pressed)
--
Best Regards,
Ulf Samuelsson
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Re: SimmStick FPGA module
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Yes, this chip is fine. You can get rid of these download cables. So the idea is
to use this USB chip to program the serial flash (in the same way as you do it
with the ByteBlaster - holding the FPGA on reset with nConfig low). Or if you
want to config it direct you could use the the JTAG interface - doning JTAG
with the FT2232C. However, for both modes you have to provide a 'special'
program and can't use Quartus anymore.

Another point: I see this module as an Java SBC and not a slave of a PC. So
I did understand Jim's suggestion to build an USB host. That means you can use
the USB to attach flash or anything else to the SBC and not the board as USB
slave to the PC. This direction was what I meant not so easy.

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You did configura the Xilinx FPGA in JTAG mode? That's very interesting.
I hope there is enough documentation about the Altera Cyclone to do the
same.

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You mean mess up with the board or with the sales numbers ;-)

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Thanks!


Martin
----------------------------------------------
JOP - a Java Processor core for FPGAs:
http://www.jopdesign.com/



Re: SimmStick FPGA module
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program.
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interface.
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Flash
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  It depends on the bandwidths, but I like Pablo's idea of a FT2232C -
there may be enough smarts between that device, and your FPGA, to
improve PC-target bandwidths for debug (single step?) and download ->
SDRAM, prior to code FLASH for final pass.
  Perhaps a 'virtual jumper' in the FPGA code, or'd with a FT2232C pin,
could select Load from USB.FIFO, or top of SerialConfig ?

  Another device that appeals for Soft-cpu is this one :
http://www.st.com/stonline/press/news/year2005/p1563m.htm
with 75MHz burst, 32 bits wide, that's 2400MB/s, vs 25-50MB/s on a SD card.
  So the SD card looses on speed, but gains on universal supply/size,
and you CAN easily remove it - hmmm... perhaps put the M58BW032 on the
other side of the PCB ?

  Maybe option the SD socket, and M58BW032, on the more complex model ?

Next, some form of Codec would be nice, what about something from this
selection ?
http://para.maxim-ic.com/compare_noj.asp?Fam=CODEC&Tree=Wireless&HP=Wireless.cfm&ln =
$5-7 for 22-60Msps ADC & DAC ?
This ties in well with a SD socket, & USB link...


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SD starts to look nice on this basis...

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modules.
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The TINI itself ? ;)
- plus as TINI also has Java path, you could get some cross-polination ?


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You are probably right, but you did ask for suggestions :)

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discuss several
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-jg


Re: SimmStick FPGA module
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program.
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interface.
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configuration
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Flash
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may be enough smarts
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(single step?) and
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From your first suggestion I thought you mean USB master on the FPGA to
use USB devices.

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select Load from
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I don't get the idea. For configuration from Flash I want the module to
run stand-alone. That means no USB connection. The FT2232C has
to be disabled in this mode and the power has to be provided through
a different pin (from the SIMM bus, e.g.).

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It was not the idea to exectue (Java) code direct from the SD card. We have
large SDRAM on board. The code is copied from the SD card (or serial Flash)
to the SDRAM prior execution. So speed is not the point. The SD card can
further act as file system.
I know that the automotive industry does like to execute direct from Flash.
They want to avoid the additional boot time due to the memory copy. They
want a boot in the ms region. However, this is not the problem for this board.

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selection ?
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http://para.maxim-ic.com/compare_noj.asp?Fam=CODEC&Tree=Wireless&HP=Wireless.cfm&ln =
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What for would you use these Codecs?

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But the SD connector is still 'large' ;-)

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modules.
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Yes, a point to consider. I don't know how large the TINI user base is.
As the TINI is a VERY slow JVM, JOP could be a fine replacement
(JOP is almost 200 times faster than the TINI). And you have an FPGA...

Martin
----------------------------------------------
JOP - a Java Processor core for FPGAs:
http://www.jopdesign.com/



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