[time-nuts] FPGA GPSDO (Was: Re: NTP jitter with Linux)

Javier Herrero jherrero at hvsistemas.es
Sat Apr 7 11:47:19 UTC 2012


El 07/04/2012 13:19, Azelio Boriani escribió:
> The Xilinx and Altera have their embedded CPUs (Microblaze and Nios) IP.
> I'm not familiar with them and don't know how much they cost. Until now I
> have developed on Xilinx 50Kgates FPGA and 128 cells CPLD with the Xilinx's
> free tools.
>
Mostly expensive for amateur use, although reduced free versions exists 
(for Nios-II it is Nios-II/e without MMU and no cache, I suppose that 
something similar for Microblaze). But both are closed-source.

There are open-source soft processors like LatticeMico32 and LEON3. I'm 
moving to one of these for a next project (not yet decided which one, 
since in this case it will be a bare-metal application, with no 
operating system, but I would like to use a processor that is supported 
by Linux distribution for the future). Linux is ported to both, and for 
LM32 (not sure if for LEON3), RTEMS also (see www.milkymist.org , an 
open source hardware and software project with an LM32 implementation on 
a Spartan 6 FPGA using RTEMS. Also there is a plethora of soft 
implementation of several processors in OpenCores (ranging from 6502 to 
OpenRISC) and also somewhere I read about an implementation of a Cray-1 
in a Spartan-3 :)

Regards,

Javier








More information about the Time-nuts_lists.febo.com mailing list