Tom, Xilinx offers the following methods: a) Periodic reload entire device, or column by column b) Absolute bit image compare, device or col by col. c) CRC digest device or col by col. The col by col methods are attractive for reducing the MTTR, but still lend themselves to red/black by device. The CRC digest is good for data reduction. Absolute images require full size map and mask images, and so eat a lot of memory. In NAND flash that might not be a problem. But then the NAND flash needs SEU protection as well. Regards, Steve At 09:02 AM 4/13/2005 -0700, Tom Biggs wrote: >I have heard of a satellite that had a non-rad hard FPGA in it. They >needed the density of a commercial part and they could handle short term >failures. So they just reloaded the FPGA every so often to clear out any >bits that got flipped by single event upsets (SEUs). > > -tom > >-----Original Message----- >From: si-list-bounce@xxxxxxxxxxxxx [mailto:si-list-bounce@xxxxxxxxxxxxx] >On Behalf Of Scott McMorrow >Sent: Wednesday, April 13, 2005 8:23 AM >To: cshroff@xxxxxxxxx >Cc: ray.anderson@xxxxxxxxxx; Bradley.S.Henson@xxxxxxxxxx; >si-list@xxxxxxxxxxxxx >Subject: [SI-LIST] SEU errors > > >Chirag, > >The current research indicates that SEU errors are possible for=20 >SRAM-based FPGA's. Whether they occur in near sea-level applications to > >any high probability is up for grabs. But it is such a concern in=20 >aircraft applications that mil-aero contractors are designing circuits=20 >with redundant FPGAs for airborne applications. > > >Regards, > >scott > > > >Scott McMorrow >Teraspeed Consulting Group LLC >121 North River Drive >Narragansett, RI 02882 >(401) 284-1827 Business >(401) 284-1840 Fax > >http://www.teraspeed.com > >Teraspeed(r) is the registered service mark of >Teraspeed Consulting Group LLC > > > >Chirag Shroff (cshroff) wrote: > > >=3D20 > >-----BEGIN PGP SIGNED MESSAGE----- > >Hash: SHA1 > > > > Our SEU research group has several test sites co-located at a number=20 > >of high-altitude astronomical observatory mountain top locations. > > > >So do you see Soft error events on these test sites ? > > > >- --Chirag Shroff > > > > =3D20 > > > >-----BEGIN PGP SIGNATURE----- > >Version: PGP 8.1 > > > >iQA/AwUBQl016InQs7uCgmQlEQJ0LwCdHq9/FovY+lXWcgQZh5CurnWlcj0An2jz > >qx+cWXizPKM90lxGzoNi9u5r > >=3D3D78SN > >-----END PGP SIGNATURE----- > >------------------------------------------------------------------ > >To unsubscribe from si-list: > >si-list-request@xxxxxxxxxxxxx with 'unsubscribe' in the Subject field > > > >or to administer your membership from a web page, go to:=20 > >//www.freelists.org/webpage/si-list > > > >For help: > >si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field > > > >List FAQ wiki page is located at: > > http://si-list.org/wiki/wiki.pl?Si-List_FAQ > > > >List technical documents are available at: > > http://www.si-list.org > > > >List archives are viewable at: =20 > > //www.freelists.org/archives/si-list > >or at our remote archives: > > http://groups.yahoo.com/group/si-list/messages > >Old (prior to June 6, 2001) list archives are viewable at: > > http://www.qsl.net/wb6tpu > > =20 > > > > > > =20 > > > >------------------------------------------------------------------ >To unsubscribe from si-list: >si-list-request@xxxxxxxxxxxxx with 'unsubscribe' in the Subject field > >or to administer your membership from a web page, go to: >//www.freelists.org/webpage/si-list > >For help: >si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field > >List FAQ wiki page is located at: > http://si-list.org/wiki/wiki.pl?Si-List_FAQ > >List technical documents are available at: > http://www.si-list.org > >List archives are viewable at: =20 > //www.freelists.org/archives/si-list >or at our remote archives: > http://groups.yahoo.com/group/si-list/messages >Old (prior to June 6, 2001) list archives are viewable at: > http://www.qsl.net/wb6tpu > =20 > >------------------------------------------------------------------ >To unsubscribe from si-list: >si-list-request@xxxxxxxxxxxxx with 'unsubscribe' in the Subject field > >or to administer your membership from a web page, go to: >//www.freelists.org/webpage/si-list > >For help: >si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field > >List FAQ wiki page is located at: > http://si-list.org/wiki/wiki.pl?Si-List_FAQ > >List technical documents are available at: > http://www.si-list.org > >List archives are viewable at: > //www.freelists.org/archives/si-list >or at our remote archives: > http://groups.yahoo.com/group/si-list/messages >Old (prior to June 6, 2001) list archives are viewable at: > http://www.qsl.net/wb6tpu > ------------------------------------------------------------------ To unsubscribe from si-list: si-list-request@xxxxxxxxxxxxx with 'unsubscribe' in the Subject field or to administer your membership from a web page, go to: //www.freelists.org/webpage/si-list For help: si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field List FAQ wiki page is located at: http://si-list.org/wiki/wiki.pl?Si-List_FAQ List technical documents are available at: http://www.si-list.org List archives are viewable at: //www.freelists.org/archives/si-list or at our remote archives: http://groups.yahoo.com/group/si-list/messages Old (prior to June 6, 2001) list archives are viewable at: http://www.qsl.net/wb6tpu