Low End FPGAs

So I'm looking at various platforms for general purpose, fairly low-end
FPGAs, and it looks like the Lattice ECP5, Xilinx Artix-7, and Altera
Cyclone V E all have options in the sort of

  * 170ish IO
  * Enough logic to do PLDy sort of tasks
  * $20ish in ~100p quantity.

I've used Vivado, and Vivado's got its issues.  I've used the latest
Quartus Prime, and Quartus Prime's got its issues.  Haven't used Diamond
yet, but I'm guessing Diamond's got its issues.

Has anyone been playing with any (or even better multiple) of these and
got any opinions one way or another on which to go with? Or do I just
roll a die?

-- 
Rob Gaddi, Highland Technology -- www.highlandtechnology.com

Email address domain is currently out of order.  See above to fix.

On 8/25/2016 8:04 PM, Rob Gaddi wrote:
> So I'm looking at various platforms for general purpose, fairly low-end
> FPGAs, and it looks like the Lattice ECP5, Xilinx Artix-7, and Altera
> Cyclone V E all have options in the sort of
>
>   * 170ish IO
>   * Enough logic to do PLDy sort of tasks
>   * $20ish in ~100p quantity.
>
> I've used Vivado, and Vivado's got its issues.  I've used the latest
> Quartus Prime, and Quartus Prime's got its issues.  Haven't used Diamond
> yet, but I'm guessing Diamond's got its issues.
>
> Has anyone been playing with any (or even better multiple) of these and
> got any opinions one way or another on which to go with? Or do I just
> roll a die?

If you are happy with Lattice you might consider the LFXP2-5E-5FTN256C. 
172 I/Os, 5 kLUTs, 18 kB (9 bit bytes) block RAM, 3 DSP blocks and 12 
multipliers.  It is Flash rather than RAM based (or more accurately 
both), so no external Flash.  The best part is it's $13 at qty 100.

Lattice also has their ice40 line which has RAM and one time 
programmable NV memory.  They have two lines, low power and high 
performance, LP8K and HX8K respectively.  Both parts have 7,680 LUTs, 32 
block RAMs (4 kbit) and no math components.

I haven't used these parts, I've used the XP series.  The Diamond 
software uses Synplicity and ActiveHDL for synthesis and simulation and 
seems to work ok.  VHDL 2008 seems to be supported pretty well.

-- 

Rick C

Rob Gaddi wrote:

> So I'm looking at various platforms for general purpose, fairly low-end
> FPGAs, and it looks like the Lattice ECP5, Xilinx Artix-7, and Altera
> Cyclone V E all have options in the sort of
> 
>   * 170ish IO
>   * Enough logic to do PLDy sort of tasks
>   * $20ish in ~100p quantity.
> 
> I've used Vivado, and Vivado's got its issues.  I've used the latest
> Quartus Prime, and Quartus Prime's got its issues.  Haven't used Diamond
> yet, but I'm guessing Diamond's got its issues.
> 
> Has anyone been playing with any (or even better multiple) of these and
> got any opinions one way or another on which to go with? Or do I just
> roll a die?
> 
The smallest Xilinx Spartan 3E is quite affordable, if you need just a 
little logic.  There's also the CoolRunner II and XC9536XL for really small 
jobs, these are only $1 - $2 each.

Jon

Jon Elson wrote:

> Rob Gaddi wrote:
>
>> So I'm looking at various platforms for general purpose, fairly low-end
>> FPGAs, and it looks like the Lattice ECP5, Xilinx Artix-7, and Altera
>> Cyclone V E all have options in the sort of
>> 
>>   * 170ish IO
>>   * Enough logic to do PLDy sort of tasks
>>   * $20ish in ~100p quantity.
>> 
>> I've used Vivado, and Vivado's got its issues.  I've used the latest
>> Quartus Prime, and Quartus Prime's got its issues.  Haven't used Diamond
>> yet, but I'm guessing Diamond's got its issues.
>> 
>> Has anyone been playing with any (or even better multiple) of these and
>> got any opinions one way or another on which to go with? Or do I just
>> roll a die?
>> 
> The smallest Xilinx Spartan 3E is quite affordable, if you need just a 
> little logic.  There's also the CoolRunner II and XC9536XL for really small 
> jobs, these are only $1 - $2 each.
>
> Jon

My concern is longevity for new designs.  Xilinx's decision to not bring
any of the Spartan family forward to Vivado sounds a whole lot like
"Well, we're not NOT supporting them, but..."

Altera's decision to drop Quartus support for Cyclone III, even though
they still support the Cyclone IV which is nothing but a die shrink, is
equally irksome.

-- 
Rob Gaddi, Highland Technology -- www.highlandtechnology.com

Email address domain is currently out of order.  See above to fix.

I've been very happy playing with Max 10. There's a dev board for 30$ which is really cheap but has 8K logic elements, sdram, etc.
https://www.arrow.com/en/products/bemicromax10/arrow-development-tools

For a medium design (Z80 CPU and peripherals) my compilation times were ~10-15 minutes if I remember correctly with the free edition of Quartus.

I also found the free included SignalTap logic analyzer very useful in debugging the design-- I've heard that Xilinx charges for the logic analyzer part which swayed me in Altera's direction.

The chip itself is also pretty cheap in small quantities (~~10$)
http://www.mouser.com/ProductDetail/Altera/10M08SCU169C8G/?qs=sGAEpiMZZMvzv9EAOJZmO9CMfHSxRLPsX%252b1%252bhuEUWwU%3d

What applications are you looking to implement and what other factors are important to you?

On Friday, August 26, 2016 at 3:11:35 PM UTC-4, Rob Gaddi wrote:
> Jon Elson wrote:
> 
> > Rob Gaddi wrote:
> >
> >> So I'm looking at various platforms for general purpose, fairly low-end
> >> FPGAs, and it looks like the Lattice ECP5, Xilinx Artix-7, and Altera
> >> Cyclone V E all have options in the sort of
> >> 
> >>   * 170ish IO
> >>   * Enough logic to do PLDy sort of tasks
> >>   * $20ish in ~100p quantity.
> >> 
> >> I've used Vivado, and Vivado's got its issues.  I've used the latest
> >> Quartus Prime, and Quartus Prime's got its issues.  Haven't used Diamond
> >> yet, but I'm guessing Diamond's got its issues.
> >> 
> >> Has anyone been playing with any (or even better multiple) of these and
> >> got any opinions one way or another on which to go with? Or do I just
> >> roll a die?
> >> 
> > The smallest Xilinx Spartan 3E is quite affordable, if you need just a 
> > little logic.  There's also the CoolRunner II and XC9536XL for really small 
> > jobs, these are only $1 - $2 each.
> >
> > Jon
> 
> My concern is longevity for new designs.  Xilinx's decision to not bring
> any of the Spartan family forward to Vivado sounds a whole lot like
> "Well, we're not NOT supporting them, but..."
> 
> Altera's decision to drop Quartus support for Cyclone III, even though
> they still support the Cyclone IV which is nothing but a die shrink, is
> equally irksome.
> 
> -- 
> Rob Gaddi, Highland Technology -- www.highlandtechnology.com
> 
> Email address domain is currently out of order.  See above to fix.

Rob Gaddi wrote:


> My concern is longevity for new designs.  Xilinx's decision to not bring
> any of the Spartan family forward to Vivado sounds a whole lot like
> "Well, we're not NOT supporting them, but..."
> 
Fortunately, Xilinx does archive their older tools.  I just had to bring 
back an ise ver 10.1 system to make a change to a legacy design on Spartan 
2E.  I'm running ise 14.7 for my current products using 95**XL and Spartan 
3A, and happy with them, no desire to update and learn any new software.
> Altera's decision to drop Quartus support for Cyclone III, even though
> they still support the Cyclone IV which is nothing but a die shrink, is
> equally irksome.
> 
Glad to know Xilinx isn't the only outfit doing this.

Jon

Emilian Miron wrote:

> I've heard that Xilinx charges for the logic
> analyzer part which swayed me in Altera's direction.
> 
No, I don't think that is true.  I'm pretty sure ChipScope is included even 
in the WebPack, although it probably has size limits or something.  At least 
for the versions I'm using.

Jon

Am Samstag, 27. August 2016 04:05:02 UTC+2 schrieb Jon Elson:
> Emilian Miron wrote:
> 
> > I've heard that Xilinx charges for the logic
> > analyzer part which swayed me in Altera's direction.
> > 
> No, I don't think that is true.  I'm pretty sure ChipScope is included even 
> in the WebPack, although it probably has size limits or something.  At least 
> for the versions I'm using.
> 
> Jon

This has changed recently, luckily... Unfortunately, the user experience of ChipScope is in no way comparable with SignalTap, at least IMHO.

Thomas

www.entner-electronics.com - Home of EEBlaster

> > My concern is longevity for new designs.  Xilinx's decision to not bring
> > any of the Spartan family forward to Vivado sounds a whole lot like
> > "Well, we're not NOT supporting them, but..."
> > 
> Fortunately, Xilinx does archive their older tools.  I just had to bring 
> back an ise ver 10.1 system to make a change to a legacy design on Spartan 
> 2E.  I'm running ise 14.7 for my current products using 95**XL and Spartan 
> 3A, and happy with them, no desire to update and learn any new software.

Also Altera allows you to download their old software. In both cases this may help you out in short term, but in long term you may have issues installing this versions on a modern system. (e.g. if you want to maintain a FLEX10K design - not sure if MAX+PLUS II installs on Win 10 64b...) (of course it is more Microsoft to blame here...)

> > Altera's decision to drop Quartus support for Cyclone III, even though
> > they still support the Cyclone IV which is nothing but a die shrink, is
> > equally irksome.
> > 
> Glad to know Xilinx isn't the only outfit doing this.
> 
> Jon

From my outside view the difference is, that Vivado does not support old devices as it is "too much of a challange" for Xilinx, while Quartus stops supporting older devices because of political decisions form Altera (which are not clear to me? Urging people into new devices? In reality it is more forcing customers to stay at older versions... For some parts it may make sense from a maintenance point of view, but as someone already mentioned e.g. Cyclone III and IV are internally the same).

Both is equally frustrating....

Thomas

www.entner-electronics.com - Home of EEBlaster

Altera: I would also consider the MAX10 family
Xilinx: The have announced Spartan-7 some time ago, but beside this (remarkingly low content) announcement, I do not know about the status of this. So it seems you have to look at Artix-7 as you already do
Lattice: MachXO2/3 should be you part

My very personal opinion on software rating:
1. Quartus (esp. small designs benefit from the "more responsive" feeling of the GUI - I am talking about 15.0 here, have not used Prime yet)
2. Vivado (Although I like the integrated simulator a lot)
3. Diamond (however, have not used it since a while)

But for sure you can get your work done with all of them, so this discussion is highly subjective.

Thomas

www.entner-electronics.com - Home of EEBlaster