RFC: ARM+FPGA tiny board

Do you have a question? Post it now! No Registration Necessary

Translate This Thread From English to

Threaded View
Hello group.

We would like you to share with us your comments and opinions about a
product we are planning to launch. Your feedback will be very helpful to
determine the interest in this kind of product, and important to establish
its development path and features (including, of course, price, so by
helping us you may be helping yourself ;^)

This is a low cost, low power little board (3"x2") we designed to use in our
own custom control & data acquisition projects, but the concept turned out
so nice and nifty that we are evaluating the possibility to commercialize it
as a line product. It currently has an AT91M42800A MCU from Atmel (ARM7TDMI
with an external bus), up to 1MB RAM, 1MB to 8MB Flash, integrated power
supply and a Xilinx SpartanIIe FPGA (XC2S50E or XC2S100E) with a
programmable clock oscillator. Expansion headers are provided for all
important board signals (120, including power pins), with top and bottom
stack mount capability.

Most MCU and FPGA pins are shared to provide a flexible interfacing
architecture. The FPGA can be used for logic interfacing, data processing,
video output and LCD interface, hardware UARTs and other kind of
communications, etc.

We would like to introduce this first as a basic kit with all the necessary
tools to get one started (core module, adapter board with serial
transceivers, wiggler-like JTAG programmers, software). The board itself is
a wonderful combo-kit for learning about embedded systems with the ARM
architecture and FPGAs. Most of the software and applications will be
provided as open source and a web site with useful information (application
notes, code and FPGA cores) will be set up. An eCos profile for the board
will be made available too.

We also have designs for a backplane and auto-configuring add-on modules
with analog and digital IOs, Ethernet interface, IrDA and RF transceivers,
CompactFlash interface, etc. Our idea is to make them available once we can
reinvest and verify enough demand for each kind of device.

The board can be configured for 1V-3.6V input operation using an efficient
step-up regulator,  targeted mainly for battery powered applications.
Another configuration allows not installing the FPGA and using a cheap LDO
regulator for cost-sensitive applications where the FPGA is not necessary
and power efficiency is not of concern.

You can take a look at some pre-production kit items at
http://www.embedded.cl/gallery/ARMermelator

In particular, you would help us a lot with your answers and suggestions for
the following:
- How much will you be willing to pay for a kit like this. How much for core
boards in quantities?
- Do you think the FPGA configuration (ie, FPGA present on the board) will
be useful for you? Would you choose this board over other similar products
because of its FPGA functionality?
- Concerning the kit, do you think a base board with integrated programmers,
serial transceivers and prototyping area would be more useful to you than an
adapter board and separated programmers?
- What kind of applications and solutions to your needs do you envision
using a board like this?
- Without knowing further details, your overall impression about this
product.

Well, thank you very much in advance. Sorry for the long post and sorry if
the content of this post sounded too much like marketing instead of
technical matters -- we are not trying to offend anyone but to help us all.

Warmest regards.


--
PabloBleyerKocik /
 pbleyer        /"Simplicity is prerequisite for reliability."
We've slightly trimmed the long signature. Click to see the full one.
Re: ARM+FPGA tiny board

Quoted text here. Click to load it
our
it
(ARM7TDMI
Quoted text here. Click to load it
necessary
is
(application
Quoted text here. Click to load it
can
for
core
programmers,
an
all.


I think the FPGA does separate it from most of the pack, though it is still
not alone. The size is quite attractive, making it lean towards a powerful
minaturized mobile application. However, the FPGA is not incredibly
power-efficient; some applications might require all the flip-flops, but a
low-power CoolRunner variation might be something to consider. They are
quite inexpensive and can fit a surprising amount of logic, I have a
four-axis (8 coil) bipolar microstepping translator and driver project that
so far fits into 128. The processor itself would probably be able to handle
many of the tasks you would use all the flip-flops for, anyway. The CPLD
also won't need to be reloaded every power cycle.

I think you what need to do is identify your competitors. In this case, I
think your main competitor is the Pocket PC series of devices, which get up
to a full day's worth of battery life, have an integrated LCD controller and
LCD, standard interfaces to memory and expansion cards, and with a 200MHz
processor and 64 megabytes of RAM can be had for less than $200. Your device
needs to make up its shortcomings in the display, memory, and standard
interface department, by pushing the programmable device aspect and large
number of high-speed user I/O. Price the device in a range where customers
won't choose instead to build their own CompactFlash interface card with a
CPLD, and end up with a more powerful system for less money. If you target
this to engineers in a production environment, you could possibly get away
with a price near $400-$500, if you have a lot of options and good support
(you've also got to compete against the popular PC104 systems, and low-power
options probably won't be a selling point). If you target to hobbyists, I
think a $175 to $250 range would be realistic though they will always buy
something cheaper if they can. Basically find a cheap ARM board and a cheap
FPGA board, and add the prices together.



Re: ARM+FPGA tiny board
[Sorry to repost, but it seems my news server screwed up again]

Quoted text here. Click to load it

 Yes, we considered a CPLD versus the FPGA. For some applications the
CPLD fits fine, but it leaves a lot of applications out. For example,
we have had applications where we need a *lot* of UARTs, you can only
fit one or two UARTs in most reasonably priced CPLDs. There is also a
benefit/cost relationship. Indeed, the Coolrunner XC2C128 costs only
~US$4 less than the Spartan XC2S100E, and the latter has far more
resources. The FPGA itself is not as power-hungry as one might think.

Quoted text here. Click to load it

 It is really not a PocketPC. You cannot put a PocketPC in an
industrial environment! The idea of the board is to use it for deeply
embedded devices, although of course you can plug an LCD and other
consumer-electronics stuff to it. We are targeting the sub-US$100
market of 8 and 16 bit module boards.

 The idea for the battery operation is that you use the low power
modes of the processor to reach weeks of battery life.

Quoted text here. Click to load it

 Yes, we will make modules and FPGA cores available for this. We know
that the 1MB RAM limit could scare many people out there, but for the
applications we have in mind there is no need for more (really -- eCos
is so configurable that it only takes the memory resources it actually
needs). The CF module, for example, will add enough memory for data
logging applications, that is a typical scenario where you need lots
of memory (eg 512MB).

Quoted text here. Click to load it

 In fact, we are targeting hobbyist and other OEMs. We are trying to
sell the core board and modules for less than US$100, and the kit in
no more than US$200.

 Thanks again for your comments, they are very valuable.

 Regards.

Re: ARM+FPGA tiny board

Quoted text here. Click to load it

Nice looking board!  How can you make a 6 layer board stuffed with memory, arm7
processor and a spartan II and sell for under $100???  I could see if you are
making several hundred to thousands....

Which board house made the board?  Digikey must be really juicing me on
pricing...

Rick



Re: ARM+FPGA tiny board
Hello Rick.

Quoted text here. Click to load it
arm7
are

 No, we are not (yet -- but fingers are crossed. ;^) Our post was trying to
analyze the demand for the product. We don't have final cost figures, but,
yes, we think will be able to sell the core in single quantities around that
amount.

Quoted text here. Click to load it

 Protos were manufactured by E-teknet (http://www.e-teknet.com /). I strongly
recommend them.

Quoted text here. Click to load it

 Digikey has improved its pricing a lot, but on some parts they are still
pricey (specially AT91 mcus in this case). You can buy packs from, eg, Avnet
(60 units) at the same price Digikey offers them at 1000 units.

 Regards.



Re: RFC: ARM+FPGA tiny board
Hi Pablo,

Interesting product. Some comments:

Quoted text here. Click to load it

IMHO, this board is a bit complicated for introductory embedded
learning purposes. And I expect it will be a bit too expensive. You'll
be competing with sub-$200 boards from Atmel and sub-$100 ARM boards
based on other ARMs. Maybe it's better marketed as a poor-man's-ASIC
:)

Quoted text here. Click to load it

I would personally pay up to about $300 for the board and
documentation. I wouldn't pay extra for a parallel port wiggler, etc.
because I already have these tools. For "production", I would only be
willing to pay around half that price for a board including FPGA. I
would suggest preloading Angel or (better) RedBoot in ROM, not
including JTAG tools with the appliance, and letting people use it the
good old way with a serial cable.

Quoted text here. Click to load it

The FPGA isn't directly useful to me - because I don't have enough
time to use it effectively (one-man team...) But it could become
useful if I could download canned applications from you - LCD
controller being the application of primary interest!

Quoted text here. Click to load it

Lose the prototyping area. Bring the signals to headers. I'm not
hacking stuff onto an eval board.

Re: RFC: ARM+FPGA tiny board
[Sorry to repost. Seems my news server screwed up.]

Hello Lewin. Thanks for replying.

snipped-for-privacy@larwe.com (Lewin A.R.W. Edwards) wrote in message
Quoted text here. Click to load it

 Yep, that's a nice comparison. ;^) However, we are trying to sell the
core module and other modules for less than US$100 (single
quantities), and the kit for something between US$150 and US$200.

 The idea of the core+module is to make modules as cheap as possible
(eg 2 layer PCBs instead of the 6 layer PCB the core has). This will
allow people to build their own custom boards cheaply too.

Quoted text here. Click to load it

 Wow, that's a lot more than the price we thought we could sell the
boards. We are pushing our costs as low as we can. We don't have all
the cost figures yet (since this will be a first full fledged
production we cannot benefit from scale economies yet), but the idea
is to make the price low cost. If we have success we expect prices to
improve.

Quoted text here. Click to load it

 Yes, that is the whole idea of it (like you said, a poor-man's ASIC.
;^) In the future we will provide FPGA cores, auto-configurable
modules and configuration tools. For now the kit will be available,
and most of the software (including HDL code) will be open source.

Quoted text here. Click to load it

 Thanks, that is worthful. We were into the discussion of how valuable
was the prototyping area for some people.

 Thanks again for your comments and suggestions!

 Regards.

Re: RFC: ARM+FPGA tiny board
On 13 Feb 2004 19:19:07 -0800, snipped-for-privacy@hotmail.com (Pablo Bleyer

Quoted text here. Click to load it


Another vote for headers.

If one of them bears some relationship to a SODIMM socket, you could
conceivably support SDRAM through a controller in the FPGA, for those
who need it. Just a thought.

- Brian

Re: RFC: ARM+FPGA tiny board
Hello Brian.

Quoted text here. Click to load it

 All the available MCU and FPGA signals have been exported to the
headers (120 pins total). The idea of dual headers is to be able to
stack modules up or down and keep things compact. We have also a
design for a backplane, where the core module fits in dual headers and
there are AGP132 connectors for the add-on modules that also have an
edge connector (these have a length of ~2.7" that fits that format).
So, yes, it's possible to have a module with SDRAMs controlled by the
FPGA, although this will take some pins of the headers for the SDRAM
control signals. If the module has an external controller that would
be better, but perhaps a cleaner choice would be to use PSRAMs.

 The extra 12 signals of the AGP132 connectors are used for
alternative voltages (eg negative voltages for bipolar DACs), and 4
pins are used for module auto-detection.

 Thanks for your comments. Regards.

Re: RFC: ARM+FPGA tiny board
Quoted text here. Click to load it

My vote would be for both headers and a proto area.  The extra square
inches of board space is not very much cost.  When it comes to the
headers, I always make the pinout compatible with the HP logic analyzer
pinout.  But not many agree with me on that.  I find it so much more
convenient to be able to plug in the pods rather than to have to clip
all those little leads on.  :)

If anyone is interested, I can provide the HP doc on how to do this.  

--

Rick "rickman" Collins

snipped-for-privacy@XYarius.com
We've slightly trimmed the long signature. Click to see the full one.
Re: RFC: ARM+FPGA tiny board
Hi Pablo,  

Interesting idea ;)

Our board is going to have an ARM and an FPGA tightly coupled as well.
But we will have a lot more of course.  

Having gone down this road before, I would recommend that you used
different devices than the two you have picked.  I think you will find
it is cheaper to use an ARM with internal Flash and RAM.  Of course how
much you need depends on your application and a SOC ARM may not have
enough.  But you can sell the board with/without the external Flash and
RAM to make a low cost version possible.  

We picked the OKI ARM chips, the ML67Q5003 in particular.  It has 32 kB
RAM and 512 kB Flash on chip.  It also has tons of IO and multiple IO
devices (UARTs, SPI, I2C, ADC...).  It will directly support SDRAM and
provides chip selects for Flash and IO devices.  

The Spartan IIE FPGAs are ok devices, but as someone else pointed out,
they are not very low power.  They also have an issue with a power on
current surge that requires 0.5 Amps of current minimum without allowing
the voltage to drop.  And all this is during the voltage ramp up
process!  Then to top it all off, these parts are not 5 volt tolerant.
There are still a lot of apps that need to interface to 5 volt signals.  

We picked the Altera EP1K series of FPGAs.  They are fairly low cost and
less power hungry than the Spartan IIE devices.  Their power on current
is much lower and the core voltage matches the OKI ARM chip.  


Pablo Bleyer wrote:
Quoted text here. Click to load it

--

Rick "rickman" Collins

snipped-for-privacy@XYarius.com
We've slightly trimmed the long signature. Click to see the full one.
Re: RFC: ARM+FPGA tiny board
Hello Rick!

Quoted text here. Click to load it

 We picked up this AT91 for its availability in low volumes, sleep
modes (internal PLL that boosts 32kHz to 32MHz) and temperature range.
Yes, we considered and are considering other devices as well, like OKI
chips (they support external SDRAM, though these are difficult to
source in industrial temp) and the LPC22XXs. If this works out perhaps
we can offer other family siblings with the same board format and
other MCUs. Nice thing is that they are all ARMs so code reusability
and compatibility is secured.
  
Quoted text here. Click to load it

 We have measured the ramp-up current of SpartanII and IIe FPGAs and
it is really not an issue with this kind of boards (of course, the
power supply was designed considering the FPGA requirements). We have
used Xilinx FPGAs in several designs, so we are confident with the
parts and we know their features and limitations. We try very hard to
design our boards with reliability in mind and we do lots of tests in
field and harsh environments (Chilean mining industry, do I need to
say more? ;^)

 In standby (MCU at 32kHz --not in sleep--, FPGA clocks halted) the
unit takes ~60mA @ 3.3V input. When the MCU is running at 32MHz the
board typically consumes ~140mA at the same voltage. FPGA consumption
varies, but for simple apps it's below 100mA working at full MCU
clock. So a typical application always at full MCU clock can run for
~10 hours with two rechargeable NiMH AA batteries. If the board enters
sleep mode power consumption can be reduced a lot and will improve
stand-alone operation considerably.

Quoted text here. Click to load it

 Yep, we know that there are a lot of 5V systems out there. We
analyzed the situation and it really was cheaper to make the core
module as simple as possible, and add a couple of 25 cent 5V tolerant
transceivers to the add-on modules that use 5V parts (and where there
is more space).
  
Quoted text here. Click to load it

 Have you measured their standby current (before configuration) and
static consumption (after configuration and halted clocks)? That would
be nice figures to compare.

 Thanks for your comments. Cheers!

PabloBleyerKocik /
 pbleyer        /"Simplicity is prerequisite for reliability."
  @embedded.cl / -- Edsger Wybe Dijkstra

Re: RFC: ARM+FPGA tiny board
Quoted text here. Click to load it

Many of the newer ARMs are available in Industrial temps (OKI only comes
in Industrial) and some work with a 32 kHz xtal (the OKI does not).  

Quoted text here. Click to load it

Unfortunately the LPC22xx are not out yet.  Only the versions with no
external bus are available.  


Quoted text here. Click to load it

Wow!  That is a lot more than other devices can do, but I guess if it is
not an issue with your application it does not matter.  The OKI part
runs at 60 MHz with less than 60 mA @ 2.5v.  Of course the FPGA current
will depend on the app inside, but we are designing with <70 mA @ 5v
target in mind.  Our sleep current is around 5 mA which is almost all
from the FPGA.  Many of our customers run from batteries and the current
is a *major* concern.  


Quoted text here. Click to load it

I guess if you have picked the Xilinx parts for other reasons that would
be true.  But the power and the 5 volt tolerance is the main reason we
picked the Altera ACEX part.  This just eliminates the extra parts and
keep the power supply simple.  We are using a couple of switched
capacitor converters to keep it as efficient as possible.  


Quoted text here. Click to load it

I have not measured it, but the numbers that Altera has given me are 100
mA startup surge and 5/10 mA static current (commercial/industrial
temps).  

--

Rick "rickman" Collins

snipped-for-privacy@XYarius.com
We've slightly trimmed the long signature. Click to see the full one.
Re: RFC: ARM+FPGA tiny board
Quoted text here. Click to load it

 Main problem is, as always, availability. There are some newer parts that
have more features than the one we are using at a similar price, but,
believe me, we laid out all the information we had on the table before we
picked up the processor.

Quoted text here. Click to load it

 The LCP21XX are supposedly to be available, but they are very difficult to
source. Waiting for the LPC22XX was simply out of the question. Also, these
devices are too new to put them out directly into production without knowing
the exact erratas. These chips look good, though, so surely we will be
evaluating them to use them in our solutions.

Quoted text here. Click to load it

 Thanks, that is a good figure to know about.

Quoted text here. Click to load it

 Well, so I guess in this case the datasheet reflects reality (not always
the case, with any vendor indeed).

 Regards.

--
PabloBleyerKocik / "Personally I don`t understand the motivation
 pbleyer        / to build robots in human form since humans are
We've slightly trimmed the long signature. Click to see the full one.
Re: RFC: ARM+FPGA tiny board
Quoted text here. Click to load it
For the JTAG interface, just add an Multi-ICE 20-pin header. Most
designers have Wiggler-like Dongle. Or if you need a better flash
programming baudrate or debugging baudrate, use the Chameleon POD with
raven_all_speeds configuration.
(note: Chameleon POD can operates as Raven, Wiggler,
Xilinx_parallel_cable, Altera_ByteBlaster, Lattice_ispDownload,
Atmel_AVR_stkxxx, configutation! ALL config for FREE, ALL in ONE Dongle)

Laurent
www.amontec.com


Re: RFC: ARM+FPGA tiny board
Quoted text here. Click to load it

Or you could just add the Xilinx coolrunner part that they are using on
the Chameleon pod and connect directly to the PC!  

--

Rick "rickman" Collins

snipped-for-privacy@XYarius.com
We've slightly trimmed the long signature. Click to see the full one.
Re: RFC: ARM+FPGA tiny board
Quoted text here. Click to load it

 Actually, we are doing something much better, but it will only see the
light once we have the necessary ROI to fund its production ;^)

 Regards.



Re: RFC: ARM+FPGA tiny board
Quoted text here. Click to load it

One thing to be aware of:  Cost, and bigtime.  <$200 gets a Spartan 2
150 board with SRAM and FLASH which fits into a gameboy advance.  Thus
the total system cost is <$300 for processor, a couple MB of memory, a
couple MB of flash, ~50 header pins, a nice little display, and a
battery power supply.

--
Nicholas C. Weaver                                 snipped-for-privacy@cs.berkeley.edu

Site Timeline