Fwd: Re: [lowrisc-dev] FPGA Recommendation

Wei Song ws327 at cam.ac.uk
Fri Jun 9 16:08:41 BST 2017

Forget to cc mail-list.  -Wei

-------- Forwarded Message --------
Subject: 	Re: [lowrisc-dev] FPGA Recommendation
Date: 	Fri, 9 Jun 2017 16:07:15 +0100
From: 	Wei Song <ws327 at cam.ac.uk>
To: 	Tobias Strauch <tobias at cloudx.cc>

So here is a list of boards we support right now:

tagged-memory-v0.1:     ZedBoard (obsolete)
untether-v0.2:          Nexys4-DDR / KC705
debug-v0.3:             Nexys4-DDR / Zedboard (need a USBUART Pmod)
minion-v0.4:            Nexys4-DDR

We still want to keep using Nexys4-DDR due to its low price.
Honest speaking, it becomes difficult as the LUT consumption is around
90% for minion-v0.4 (one rocket + one PULP).

Jonathan has tried the Nexys-Video board but with issues in UART and
QSPI Flash if I remember it right.

VC707 or KC705 is too expensive for most people, so even if we support
it, another low-cost board should be chosen as well.

Hopefully there is no need to change in the near future; however, if we
must, I do not have a clear answer right now.


On 09/06/2017 05:18, Tobias Strauch wrote:
> Wei, I try to follow statements from the lowRISC guys closely, but I’m still puzzled:
> What is the demo installation board for your next release, if you want to use all the beautiful features (tagged, minions, debug), that come with it ? I think Alex mentioned the vc707 at the 5th WS, but please confirm.
> Thanks a lot, Tobias
> PS: Looking forward to your release ...
>> Wei Song <ws327 at cam.ac.uk> hat am 8. Juni 2017 um 11:20 geschrieben:
>> Hello Alisson,
>> This is not a direct recommendation but just a note.
>> We do not support the Xilinx zc706 dev board. To be more specific, we do
>> not direct support any Zynq FPGA after our 2016 releases. Recently
>> Furkan has ported out debug-v0.3 to Zedboard, but the ARM core is not used.
>> For lowRISC, we would recommend pure FPGA dev boards which use Kintex or
>> Virtex FPGAs.
>> The recommended board right now is Nexys4-DDR, which still has around
>> 30% area left if you get rid of the tagged memory, minion and trace
>> debugger. I think this might be enough to have a BOOM core replacing the
>> Rocket one.
>> The price for Nexys4-DDR is around 320 USD from Digilent.
>> Best regards,
>> Wei
>> On 07/06/2017 21:53, Alisson Linhares wrote:
>>> Hi everyone,
>>> I want to buy an FPGA board to work with LowRISC. However, the FPGA needs
>>> to be  large enough to fit a BOOM core. The zc706 is too expensive for me.
>>> Therefore, I'm looking for a cheaper alternative.
>>> Does anyone have any suggestion?
>>> Thanks.

More information about the lowrisc-dev mailing list