Looking for an extremely cheap FPGA board (in quantity, acad

Hi all,
I'm looking for a sub-$20 FPGA board (including everything needed to actually use it).
Requirements:
* The device must have reasonable free software that can
handle schematic capture and Verilog (Altera and Xilinx
would be easily sufficient).
* Can manage at least 1K gates and 20 flip-flops.

Strongly desired:
* At least one debounced button useable on a GPIO line (not reset
for example)
* At least six switches readable by the FPGA.
* At least six LEDs writable by the FPGA.
* At least four GPIO pins that are reasonably accessible.
* Actually costing closer to $10.
* Can power off of USB without any other supply.
* Can manage at least 5K gates and 50 flip-flops.


Would prefer:
* At least twice as much I/O as described above. More is better.
* Compatible at some level with some larger FPGA line
(Altera DEx line in an ideal world).

I'm going to go vendor shopping in a few weeks, but I thought I'd see
if anyone knows of anything close to this that's on the market.

We'd be looking at around 5K-15K ordered, all for academic purposes.
Failing finding a board, we are willing to design and manufacture our
own (as a far second choice). So suggestions on parts would be welcome.

Also, any thoughts on using a cheap microcontroller to emulate
an FPGA would be of interest.

I've found some things that aren't all that close.
* Digilent C-Mod -- $22 in quantity of 1, needs external programmer,
no I/O on-board AFAICT.
* Polmaddie2. No switches, way too much $$$, but pretty good otherwise.
Way more GPIO/FPGA than we need.


Thanks in advance,
Mark

 

[Gabor]

On 9/9/2012 12:20 PM, brehob@gmail.com wrote:

Hi all,
I'm looking for a sub-$20 FPGA board (including everything needed to actually use it).
Requirements:
* The device must have reasonable free software that can
handle schematic capture and Verilog (Altera and Xilinx
would be easily sufficient).
* Can manage at least 1K gates and 20 flip-flops.

Strongly desired:
* At least one debounced button useable on a GPIO line (not reset
for example)
* At least six switches readable by the FPGA.
* At least six LEDs writable by the FPGA.
* At least four GPIO pins that are reasonably accessible.
* Actually costing closer to $10.
* Can power off of USB without any other supply.
* Can manage at least 5K gates and 50 flip-flops.


Would prefer:
* At least twice as much I/O as described above. More is better.
* Compatible at some level with some larger FPGA line
(Altera DEx line in an ideal world).

I'm going to go vendor shopping in a few weeks, but I thought I'd see
if anyone knows of anything close to this that's on the market.

We'd be looking at around 5K-15K ordered, all for academic purposes.
Failing finding a board, we are willing to design and manufacture our
own (as a far second choice). So suggestions on parts would be welcome.

Also, any thoughts on using a cheap microcontroller to emulate
an FPGA would be of interest.

I've found some things that aren't all that close.
* Digilent C-Mod -- $22 in quantity of 1, needs external programmer,
no I/O on-board AFAICT.
* Polmaddie2. No switches, way too much $$$, but pretty good otherwise.
Way more GPIO/FPGA than we need.


Thanks in advance,
Mark

The closest I've seen is a number of Lattice eval boards like the

MachXO2 "Pico" board for about $29. I've always suspected that the
price of these boards is already somewhat artificially low in order
to win seats for their devices. It's not clear that you will get
a better price in volume, but I would think Lattice is a good place
to start for low cost FPGA's or boards.

Regards,
Gabor

 

[Tim Wescott]

On Sun, 09 Sep 2012 09:20:03 -0700, brehob wrote:

Hi all,
I'm looking for a sub-$20 FPGA board (including everything needed to
actually use it). Requirements:
* The device must have reasonable free software that can
handle schematic capture and Verilog (Altera and Xilinx would be
easily sufficient).
* Can manage at least 1K gates and 20 flip-flops.

Strongly desired:
* At least one debounced button useable on a GPIO line (not reset
for example)
* At least six switches readable by the FPGA. * At least six LEDs
writable by the FPGA. * At least four GPIO pins that are reasonably
accessible. * Actually costing closer to $10.
* Can power off of USB without any other supply. * Can manage at
least 5K gates and 50 flip-flops.


Would prefer:
* At least twice as much I/O as described above. More is better. *
Compatible at some level with some larger FPGA line
(Altera DEx line in an ideal world).

I'm going to go vendor shopping in a few weeks, but I thought I'd see if
anyone knows of anything close to this that's on the market.

We'd be looking at around 5K-15K ordered, all for academic purposes.
Failing finding a board, we are willing to design and manufacture our
own (as a far second choice). So suggestions on parts would be welcome.

Also, any thoughts on using a cheap microcontroller to emulate an FPGA
would be of interest.

I've found some things that aren't all that close.
* Digilent C-Mod -- $22 in quantity of 1, needs external programmer,
no I/O on-board AFAICT.
* Polmaddie2. No switches, way too much $$$, but pretty good
otherwise.
Way more GPIO/FPGA than we need.


Thanks in advance,
Mark

When you get as far as vendor-shopping, don't forget Avnet. I think most
of their stuff starts at $100 and goes up from there, but you never know.

Ditto SparkFun, for the opposite reason -- if they had anything FPGA,
they'd probably have something in the price range you want. But I
wouldn't bet anything that they actually have that.

--
My liberal friends think I'm a conservative kook.
My conservative friends think I'm a liberal kook.
Why am I not happy that they have found common ground?

Tim Wescott, Communications, Control, Circuits & Software
http://www.wescottdesign.com

 

[Frank Buss]

Gabor wrote:

The closest I've seen is a number of Lattice eval boards like the
MachXO2 "Pico" board for about $29. I've always suspected that the
price of these boards is already somewhat artificially low in order
to win seats for their devices. It's not clear that you will get
a better price in volume, but I would think Lattice is a good place
to start for low cost FPGA's or boards.

The Pico board has many unecessary components, like the FTDI chip,
accelerometer and the 1.2 V voltage regulator.

There are Lattice FPGAs with 3.3 V only. The LCMXO2-640HC-4TG100C for
$4.72 at Digikey should be sufficient. It has 640 LUTs, so it should be
possible to implement 1k gates with it (because sometimes multiple gates
can be integrated in one LUT). 50 flip-flops is no problem at all.

For the USB connection you could use the MC9S08JS16L, which I've used
for http://www.frank-buss.de/joystickadapter/ and which costs less than
$1. This microcontroller can program the FPGA at boot time, if you add a
SPI flash for $2, or without a Flash just from the USB port. Crystal
oscillator, DIP switches, LEDs etc. should be less than $10 for all
parts, so $20 for a fully populated PCB should be possible, if you
develop it yourself. A smart student could do it, to save development cost.

--
Frank Buss, http://www.frank-buss.de
electronics and more: http://www.youtube.com/user/frankbuss

 

[hamilton]

// Snip

It would seem that if this board is for "academic use" you could have a
student design this for you and as a class project have it built by the
students.

You really need to pick a chip that meets your "class room" requirements
for functionality first.

Not cost first.

Also,

What do you expect to teach.

Just like in any product development, What do you expect to do with this
thing, who do you expect to sell it to.

My $0.02

hamilton

 

[Gabor]

On 9/9/2012 5:30 PM, Frank Buss wrote:

Gabor wrote:
The closest I've seen is a number of Lattice eval boards like the
MachXO2 "Pico" board for about $29. I've always suspected that the
price of these boards is already somewhat artificially low in order
to win seats for their devices. It's not clear that you will get
a better price in volume, but I would think Lattice is a good place
to start for low cost FPGA's or boards.

The Pico board has many unecessary components, like the FTDI chip,
accelerometer and the 1.2 V voltage regulator.

Actually the FTDI chip is the programming adapter as well as a serial
port for this board. The original desire was for a board that came
with everything required to program it. In this case the PicoBoard
is powered by USB, and programmed with the same USB adapter. It
may not have needed the serial port, but I'll take it as an added
bonus.

All of the analog stuff is just so they can demo the "low power"
of the MachXO2 part. You could always ask for partially stuffed
boards if you want to get into a volume deal. The capacitive buttons
are also unnecessary, but better than no buttons.

In any case an FTDI chip (maybe a simpler one than that on this board)
is usually a good idea when you want the board to be programmed without
an extra JTAG cable (usually much more expensive than these boards).

There are Lattice FPGAs with 3.3 V only. The LCMXO2-640HC-4TG100C for
$4.72 at Digikey should be sufficient. It has 640 LUTs, so it should be
possible to implement 1k gates with it (because sometimes multiple gates
can be integrated in one LUT). 50 flip-flops is no problem at all.

For the USB connection you could use the MC9S08JS16L, which I've used
for http://www.frank-buss.de/joystickadapter/ and which costs less than
$1. This microcontroller can program the FPGA at boot time, if you add a
SPI flash for $2, or without a Flash just from the USB port. Crystal
oscillator, DIP switches, LEDs etc. should be less than $10 for all
parts, so $20 for a fully populated PCB should be possible, if you
develop it yourself. A smart student could do it, to save development cost.

 

[Mark Brehob]

On Sep 9, 5:30 pm, Frank Buss <f...@frank-buss.de> wrote:

Gabor wrote:
The closest I've seen is a number of Lattice eval boards like the
MachXO2 "Pico" board for about $29. I've always suspected that the
price of these boards is already somewhat artificially low in order
to win seats for their devices.  It's not clear that you will get
a better price in volume, but I would think Lattice is a good place
to start for low cost FPGA's or boards.

The Pico board has many unecessary components, like the FTDI chip,
accelerometer and the 1.2 V voltage regulator.

There are Lattice FPGAs with 3.3 V only. The LCMXO2-640HC-4TG100C for
$4.72 at Digikey should be sufficient. It has 640 LUTs, so it should be
possible to implement 1k gates with it (because sometimes multiple gates
can be integrated in one LUT). 50 flip-flops is no problem at all.

For the USB connection you could use the MC9S08JS16L, which I've used
forhttp://www.frank-buss.de/joystickadapter/and which costs less than
$1. This microcontroller can program the FPGA at boot time, if you add a
SPI flash for $2, or without a Flash just from the USB port. Crystal
oscillator, DIP switches, LEDs etc. should be less than $10 for all
parts, so $20 for a fully populated PCB should be possible, if you
develop it yourself. A smart student could do it, to save development cost.

Yep, I'm guessing we will have to design it ourselves, but I'm hoping

to find something off-the-shelf (always ideal if what you want already
exists). That said, we'll probably need to design it ourselves so
we'll need to find parts. Your suggestions are a good starting point,
thanks! The LCMXO2-640HC-4TG100C is a bit more than we need in terms
of I/O and memory, but otherwise looks nearly ideal.

Still hoping a board exists...

Thanks,
Mark

--
Frank Buss,http://www.frank-buss.de
electronics and more:http://www.youtube.com/user/frankbuss

 

[Mark Brehob]

On Sep 9, 5:42 pm, hamilton <hamil...@nothere.com> wrote:

// Snip

It would seem that if this board is for "academic use" you could have a
student design this for you and as a class project have it built by the
students.
Yep, that's the backup plan.

You really need to pick a chip that meets your "class room" requirements
for functionality first.

Not cost first.
Sadly, the top-level requirement is likely going to be cost. That is,

we'll have a fixed budget and need to do as much as we can within that
budget. I agree it's not the ideal way to proceed, and the amount for
the fixed budget is unclear at this time ($10-$20/unit is a safe bet
though).

What we are doing right now is exploring if we can possibly do the
labs we want to do given the budget we think we have. The key
question is "is this doable given the cost constraints", where "this"
is mildly flexible (thus the I/O constraints being only rough).

Also,

What do you expect to teach.

http://www.eecs.umich.edu/courses/eecs270/labs.html is what we _want_
to do. Right now on a DE2 board. The labs cover the standard basics
as well as a bit of interfacing. Some parts of the labs as written
are the way they are because of the board we have.

Just like in any product development, What do you expect to do with this
thing, who do you expect to sell it to.

What: the labs above (with some reduced I/O requirements including
losing the 7-seg displays).
Who: Anyone taking the class on-line, including those with extremely
limited budgets (third-world).

Mark

My $0.02

hamilton
Thanks!

 

[hamilton]

On 9/9/2012 5:09 PM, Mark Brehob wrote:

On Sep 9, 5:42 pm, hamilton <hamil...@nothere.com> wrote:
// Snip

Not cost first.
Sadly, the top-level requirement is likely going to be cost. That is,

This is always the argument with commercial products too.

But you still need to have a spec!

Lets be real, your on a shoestring budget with a DE2 diet ;-).

The PCB and pin headers will burn thru half of your $20.

A board with one chip onboard (i.e. LCMXO2-256HC-4TG100C $3.40 100s),
a USB connector, a 3.3V voltage regulator, a few loose passive parts and
you are done.

I would enjoy building a board like this, but I do not have an
advertising budget to pay for it.

Digikey part# ea@100pcs total

220-1425-ND 3.40 340.00 LCMXO2-256HC-4TG100C
ED90341CT-ND 0.92 92.00 CONN RECEPT MINI-USB TYPE B SMT
497-1236-1-ND 0.287 28.74 IC REG LDO 3.3V .95A D-PAK
PCB (2.5" x 2.1") 8.50 850.00 PCB I had quoted with PCBcart a few weeks ago
A26509-40-ND 1.402 140.25 CONN HDR BRKWAY .100 40POS VERT

total 1,450.99

Here is $14.51 per board for most of the components.

There may be some savings here, but the remaining passive components
will take care of that.

If I were to build a board like this, I would have to charge 3x the cost
of parts to make it worth my while.

And I would require you to buy all 100.


On the other side of the coin:

Digikey part# Qua = 1
220-1298-ND $29.99 BOARD BREAKOUT MACHXO2

http://www.latticesemi.com/documents/EB68.pdf

Has all you want, and they have an advertising budget.

This sounds like a great opportunity to teach a little entrepreneurship.

This was a fun exercise, maybe you can use it in your class.

I bet you can write on your school letter head and ask for 100 samples
of each of the parts.

You will still need to design a PCB and have it fabricated.


Good luck

hamilton

 

[Simon]

I think you're in luck...

I was browsing around earlier today trying to figure out if I could do realtime video-rate JPEG encoding on a DSP instead of having to code it up in verilog, and ran across this...

http://www.nuhorizons.com/development/board.asp?product=Lattice-ICE40LP1K-BLINK-Evaluation-Kit

For $20, you get:

- 4 capacitive buttons. I guess you still have to 'debounce' capacitive buttons...
- 63 i/o on breadboard-friendly 0.1" headers. You'll have to supply the headers.
- can power off the USB
- has ~1K logic cells (lut+flip-flop)
- comes with USB cable & software can be downloaded.

Assuming you can solder some headers onto the board, switches can be replaced by jumpers, and 63 i/o is actually really generous at this sort of level. Most of the entry-level boards are seriously miserly in comparison.

On the downside, you'd probably not get much of a bulk discount - I'm guessing they're already cut to the bone at this price...

Just FYI - not a recommendation since I've never used Lattice before, but thought you'd be interested.

Simon

 

[Frank Buss]

hamilton wrote:>

Digikey part# ea@100pcs total

220-1425-ND 3.40 340.00 LCMXO2-256HC-4TG100C
ED90341CT-ND 0.92 92.00 CONN RECEPT MINI-USB TYPE B SMT
497-1236-1-ND 0.287 28.74 IC REG LDO 3.3V .95A D-PAK
PCB (2.5" x 2.1") 8.50 850.00 PCB I had quoted with PCBcart a
few weeks ago
A26509-40-ND 1.402 140.25 CONN HDR BRKWAY .100 40POS VERT

total 1,450.99

Here is $14.51 per board for most of the components.

Is the $8.50 the price for the PCB only, without reflow soldering of the
components? Would be expensive. Even just 10 boards are much cheaper
here (double sided)

http://imall.iteadstudio.com/open-pcb/pcb-prototyping.html

And how do you program the FPGA? I don't think that you can attach the
USB port to the MachXO2, you need at least a chip to convert the
differential signal to digital, but you can't fit a full USB device
logic inside such a small FPGA, if you want to do some other useful
things with it. I would add a $1 USB microcontroller, but this means
some software development.

For the requested number of >5k devices of course it gets even cheaper,
because usually there is some setup cost of $500-$1000 for reflow
soldering and the parts get cheaper, too.

--
Frank Buss, http://www.frank-buss.de
electronics and more: http://www.youtube.com/user/frankbuss

 

[hamilton]

On 9/10/2012 4:09 AM, Frank Buss wrote:

hamilton wrote:
Digikey part# ea@100pcs total

220-1425-ND 3.40 340.00 LCMXO2-256HC-4TG100C
ED90341CT-ND 0.92 92.00 CONN RECEPT MINI-USB TYPE B SMT
497-1236-1-ND 0.287 28.74 IC REG LDO 3.3V .95A D-PAK
PCB (2.5" x 2.1") 8.50 850.00 PCB I had quoted with PCBcart a
few weeks ago
A26509-40-ND 1.402 140.25 CONN HDR BRKWAY .100 40POS VERT

total 1,450.99

Here is $14.51 per board for most of the components.

Is the $8.50 the price for the PCB only, without reflow soldering of the
components? Would be expensive. Even just 10 boards are much cheaper
here (double sided)

http://imall.iteadstudio.com/open-pcb/pcb-prototyping.html

The board I had quoted was for a four layer board (RHOS).
My error, the PCB I had quoted was also a 3x3 panel.
So the cost per board would be half what I figured.
( I was using a 2x2 panel in my original calculation)

I did not look up how the LCMXO2 was programmed, so some sort of
programmer will add a few more dollars.

The 3x cost multiplier was to include reflow of the boards.

Quoting a PCB project can get complicated without a spec to follow.

There is also a bottom line here.

Who is going to put up the capital to have these things built.

Some one like myself would have to put up over $2,000, with no guarantee
of sales.

With out a spec to follow, the customer may not like what I built and I
would have to sit on these things.

So I may be out $2k, not a good business model. ;-)

And how do you program the FPGA? I don't think that you can attach the
USB port to the MachXO2, you need at least a chip to convert the
differential signal to digital, but you can't fit a full USB device
logic inside such a small FPGA, if you want to do some other useful
things with it. I would add a $1 USB microcontroller, but this means
some software development.

For the requested number of >5k devices of course it gets even cheaper,
because usually there is some setup cost of $500-$1000 for reflow
soldering and the parts get cheaper, too.

 

[AMDyer@gmail.com]

On Sunday, September 9, 2012 12:06:12 PM UTC-5, Gabor wrote:

On 9/9/2012 12:20 PM, brehob@gmail.com wrote:

Hi all,

I'm looking for a sub-$20 FPGA board (including everything needed to actually use it).

Requirements:

* The device must have reasonable free software that can

handle schematic capture and Verilog (Altera and Xilinx

would be easily sufficient).

* Can manage at least 1K gates and 20 flip-flops.



Strongly desired:

* At least one debounced button useable on a GPIO line (not reset

for example)

* At least six switches readable by the FPGA.

* At least six LEDs writable by the FPGA.

* At least four GPIO pins that are reasonably accessible.

* Actually costing closer to $10.

* Can power off of USB without any other supply.

* Can manage at least 5K gates and 50 flip-flops.





Would prefer:

* At least twice as much I/O as described above. More is better.

* Compatible at some level with some larger FPGA line

(Altera DEx line in an ideal world).



I'm going to go vendor shopping in a few weeks, but I thought I'd see

if anyone knows of anything close to this that's on the market.



We'd be looking at around 5K-15K ordered, all for academic purposes.

Failing finding a board, we are willing to design and manufacture our

own (as a far second choice). So suggestions on parts would be welcome.



Also, any thoughts on using a cheap microcontroller to emulate

an FPGA would be of interest.



I've found some things that aren't all that close.

* Digilent C-Mod -- $22 in quantity of 1, needs external programmer,

no I/O on-board AFAICT.

* Polmaddie2. No switches, way too much $$$, but pretty good otherwise.

Way more GPIO/FPGA than we need.





Thanks in advance,

Mark



The closest I've seen is a number of Lattice eval boards like the

MachXO2 "Pico" board for about $29. I've always suspected that the

price of these boards is already somewhat artificially low in order

to win seats for their devices. It's not clear that you will get

a better price in volume, but I would think Lattice is a good place

to start for low cost FPGA's or boards.

Having been struggling with the MachXO2 for the past few months, I'd suggest doing a thorough eval before jumping in with both feet.

While it has a lot of nifty advertised features, not all of them work well, and some (i2c slave) are quite badly broken. Documentation is mostly okay, but very spread out and not indexed well, with some rough spots.

While this is a fine introduction to the life of a working engineer, it may get in the way of the concepts you're trying to teach . The basic IO, logic and ram functions seem to work as expected, these seem to be mostly copies of previous generations.

Their no cost licenses are valid for one year, so they may also change their policies on 'free' licensing or the included tool set at some future point and leave you with no good way out.

 

[Frank Buss]

AMDyer@gmail.com wrote:

Having been struggling with the MachXO2 for the past few months, I'd suggest doing a thorough eval before jumping in with both feet.

While it has a lot of nifty advertised features, not all of them work well, and some (i2c slave) are quite badly broken. Documentation is mostly okay, but very spread out and not indexed well, with some rough spots.

While this is a fine introduction to the life of a working engineer, it may get in the way of the concepts you're trying to teach . The basic IO, logic and ram functions seem to work as expected, these seem to be mostly copies of previous generations.

Their no cost licenses are valid for one year, so they may also change their policies on 'free' licensing or the included tool set at some future point and leave you with no good way out.

I think the license question is no problem, unless Lattice, Altera and
Xilinx all decide to change it.

--
Frank Buss, http://www.frank-buss.de
electronics and more: http://www.youtube.com/user/frankbuss

 

[rickman]

On 9/10/2012 9:56 AM, AMDyer@gmail.com wrote:

Having been struggling with the MachXO2 for the past few months, I'd suggest doing a thorough eval before jumping in with both feet.

While it has a lot of nifty advertised features, not all of them work well, and some (i2c slave) are quite badly broken. Documentation is mostly okay, but very spread out and not indexed well, with some rough spots.

While this is a fine introduction to the life of a working engineer, it may get in the way of the concepts you're trying to teach . The basic IO, logic and ram functions seem to work as expected, these seem to be mostly copies of previous generations.

Their no cost licenses are valid for one year, so they may also change their policies on 'free' licensing or the included tool set at some future point and leave you with no good way out.

I've been down this road with Lattice before. The license "expires" in
a year but they can renew it indefinitely because there is no additional
cost to them. They can also license it to as many computers as you wish
so don't worry about what happens when you replace that old laptop. You
won't get updates after the first year which can be a blessing actually.
If it ain't broke...

I haven't tried the new Diamond software yet.

Rick

 

[Jon Elson]

AMDyer@gmail.com wrote:

Having been struggling with the MachXO2 for the past few months, I'd
suggest doing a thorough eval before jumping in with both feet.

Well, since the OP's logic requirements are so low, he might look at
the Xilinx XC95xxXL and XC2R "CoolRunner" CPLDs. The smallest of these
devices run slightly over US $1, and have over 30 I/O pins. You'd
need something to handle the USB-JTAG conversion for programming,
there are a number of chips that can do this. I use the Xilinx
Parallel Cable III, which is just a 74HC125 and about 6 small
components (res, cap, diode) and the schematic is online. If your
project doesn't actually need USB connectivity, you could build the
circuit of the Parallel Cable III onto the board for under $1 in parts.
It only connects about 5 wires to the PC parallel port.
These CPLD chips have a bit different architecture than an FPGA, but
the Xilinx tools handle all the synthesis and mapping anyway, so it
doesn't matter much. They are more efficient for wide gates like address
comparators, but have fewer FFs than an FPGA. Still the 9536 has 36 FF's,
the 9572 would have 72. I think the coolrunner comes with 64, 128 and
up.

Jon

 

[rickman]

On 9/10/2012 4:17 PM, Jon Elson wrote:

AMDyer@gmail.com wrote:



Having been struggling with the MachXO2 for the past few months, I'd
suggest doing a thorough eval before jumping in with both feet.

Well, since the OP's logic requirements are so low, he might look at
the Xilinx XC95xxXL and XC2R "CoolRunner" CPLDs. The smallest of these
devices run slightly over US $1, and have over 30 I/O pins. You'd
need something to handle the USB-JTAG conversion for programming,
there are a number of chips that can do this. I use the Xilinx
Parallel Cable III, which is just a 74HC125 and about 6 small
components (res, cap, diode) and the schematic is online. If your
project doesn't actually need USB connectivity, you could build the
circuit of the Parallel Cable III onto the board for under $1 in parts.
It only connects about 5 wires to the PC parallel port.
These CPLD chips have a bit different architecture than an FPGA, but
the Xilinx tools handle all the synthesis and mapping anyway, so it
doesn't matter much. They are more efficient for wide gates like address
comparators, but have fewer FFs than an FPGA. Still the 9536 has 36 FF's,
the 9572 would have 72. I think the coolrunner comes with 64, 128 and
up.

Jon

If you build the Parllel Cable III into your product, what will you
connect it to? I don't think they have built a PC with a parallel port
in a number of years and my understanding is that the drivers for USB
parallel ports don't work properly with bit banging software like this.
Am I mistaken? Is this a workable solution?

Rick

 

[Jon Elson]

rickman wrote:

If you build the Parllel Cable III into your product, what will you
connect it to? I don't think they have built a PC with a parallel port
in a number of years and my understanding is that the drivers for USB
parallel ports don't work properly with bit banging software like this.
Am I mistaken? Is this a workable solution?
I have no idea about the USB-parport, but you CAN get computers with real

parallel ports, just not on laptops. I use the parallel port for lots
of interconnect projects, and the Intel D525 chipset still has parport
support, if the motherboard maker chooses to bring it out. For this
reason, we use a lot of Intel D525 (Atom) motherboards in projects.

Jon

 

[MK]

On 16/09/2012 16:53, Mark Brehob wrote:

On Sep 10, 2:07 am, Simon <goo...@gornall.net> wrote:
I think you're in luck...

I was browsing around earlier today trying to figure out if I could do realtime video-rate JPEG encoding on a DSP instead of having to code it up in verilog, and ran across this...

http://www.nuhorizons.com/development/board.asp?product=Lattice-ICE40...

For $20, you get:

- 4 capacitive buttons. I guess you still have to 'debounce' capacitive buttons...
- 63 i/o on breadboard-friendly 0.1" headers. You'll have to supply the headers.
- can power off the USB
- has ~1K logic cells (lut+flip-flop)
- comes with USB cable & software can be downloaded.

Assuming you can solder some headers onto the board, switches can be replaced by jumpers, and 63 i/o is actually really generous at this sort of level. Most of the entry-level boards are seriously miserly in comparison.

On the downside, you'd probably not get much of a bulk discount - I'm guessing they're already cut to the bone at this price...

Just FYI - not a recommendation since I've never used Lattice before, but thought you'd be interested.

Simon

That is _really_ close to what we are looking for, just the headers as
switches thing doesn't quite work. And I'd really like a bit more
output LEDs. But very encouraging that what we want is possible,
thanks so much for the pointer!

Mark

Mark - you asked earlier about Lattice Diamond software. I've used
Lattice parts a lot for the last 5 years and Diamond since it came out.
It works fine, not perfect, and nothing like as many whizzo features as
the Xilinx stuff but it's cheap and it doesn't crash (at least for me.)

I would much rather work with Lattice parts than X or A, it's all well
short of the bleeding edge and for just getting the job done at a
reasonable cost it's fine.

Michael Kellett

 

[Mark Brehob]

On Sep 10, 12:48 pm, rickman <gnu...@gmail.com> wrote:

On 9/10/2012 9:56 AM, AMD...@gmail.com wrote:



Having been struggling with the MachXO2 for the past few months, I'd suggest doing a thorough eval before jumping in with both feet.

While it has a lot of nifty advertised features, not all of them work well, and some (i2c slave) are quite badly broken.  Documentation is mostly okay, but very spread out and not indexed well, with some rough spots.

While this is a fine introduction to the life of a working engineer, it may get in the way of the concepts you're trying to teach .  The basic IO, logic and ram functions seem to work as expected, these seem to be mostly copies of previous generations.

Their no cost licenses are valid for one year, so they may also change their policies on 'free' licensing or the included tool set at some future point and leave you with no good way out.

I've been down this road with Lattice before.  The license "expires" in
a year but they can renew it indefinitely because there is no additional
cost to them.  They can also license it to as many computers as you wish
so don't worry about what happens when you replace that old laptop.  You
won't get updates after the first year which can be a blessing actually.
  If it ain't broke...

I haven't tried the new Diamond software yet.

Rick

Humm, it's sounding like Lattice is going to be the way to go unless I
can get support from Altera or Xilinx (something I'll pursue if this
gets out of the "idea" stage).

Has anyone worked with Lattice Diamond? How does it compare to the
software from Xilinx and Altera? I've been burned by some "bad" FPGA
software in the past (not horrible, just too steep of a learning curve
for the classroom) and would _really_ like the ability to do schematic
capture in addition to Verilog...

Thanks again to everyone for their responses, this has been really
useful!
Mark