Re: [psas-avionics] Avionics vs satellite design

2007-06-09 Thread Andrew Greenberg
> Not really; amsat often uses COTS chips that aren't stable under > radiation, but which exhibit known (and reversable) failure modes. > SA1100 chips with cache disabled and using SRAM for memory will crash, > but avoid lockups and so a smaller house-keeping processor can reset the > system as nee

Re: [psas-avionics] Avionics vs satellite design

2007-06-08 Thread Keith Packard
On Fri, 2007-06-08 at 11:43 -0700, Andrew Greenberg wrote: > Space rated parts are necessary for standard duration space missions. Not really; amsat often uses COTS chips that aren't stable under radiation, but which exhibit known (and reversable) failure modes. SA1100 chips with cache disabled an

[psas-avionics] Avionics vs satellite design

2007-06-08 Thread Andrew Greenberg
Space rated parts are necessary for standard duration space missions. Short duration missions are different, as evidenced by many a CubeSat that use pretty standard COTS parts. Rather than building a standard duration satellite, I wonder what we can do to our current avionics system to make it mor