embedded Linux for Rabbit 3000 ?

Started by April 14, 2004
Hello, everyone , is there a port of linux for Rabbit 3000
microprocessor ?

Thanks in advance.

REMOVE_NOSPAM_tpkcbq@singnet.com.sg wrote:
> > Hello, everyone , is there a port of linux for Rabbit 3000 > microprocessor ?
That would probably be a generally useful thing, but is unlikely to happen since the Rabbit is not binary compatible with the Z180. Any such system would probably be quite slow, because process switching in the Z180 family is not trivial. -- Chuck F (cbfalconer@yahoo.com) (cbfalconer@worldnet.att.net) Available for consulting/temporary embedded and systems. <http://cbfalconer.home.att.net> USE worldnet address!
CBFalconer wrote:
> That would probably be a generally useful thing, but is unlikely > to happen since the Rabbit is not binary compatible with the > Z180. Any such system would probably be quite slow, because > process switching in the Z180 family is not trivial.
uClinux might be portable since there's no PMMU on the rabbit. Performance would likely suck since (a) there's only an 8-bit wide data bus off-chip and (b) no internal memory and (c) no instruction cache. So the rabbit runs as fast as its byte-wide memory chips, and no faster. A rabbit with a modern DRAM controller and/or some on-chip fast static ram might be interesting, but I won't hold my breath - rabbit still hasn't added FIFOs on its UARTs. A couple of years back Zilog was hinting that they would have some flavor of linux available shortly for their eZ80. To date, linux hasn't appeared on it. The eZ80 would likely run uClinux slowly for (a) and (c). Personally, I can't think of any CPU that runs linux and maintains binary compatibility with the Z180. A better project, IMHO, than uClinux on a Rabbit would a quality free C compiler that targets the Rabbit. GCC, SDCC, or LCC would be places to start. A good companion project would be a software emulator, ala MESS or MAME. Kelly
Kelly Hall wrote:
> > CBFalconer wrote: > > That would probably be a generally useful thing, but is unlikely > > to happen since the Rabbit is not binary compatible with the > > Z180. Any such system would probably be quite slow, because > > process switching in the Z180 family is not trivial. > > uClinux might be portable since there's no PMMU on the rabbit. > Performance would likely suck since (a) there's only an 8-bit wide data > bus off-chip and (b) no internal memory and (c) no instruction cache. > So the rabbit runs as fast as its byte-wide memory chips, and no faster. > A rabbit with a modern DRAM controller and/or some on-chip fast static > ram might be interesting, but I won't hold my breath - rabbit still > hasn't added FIFOs on its UARTs. > > A couple of years back Zilog was hinting that they would have some > flavor of linux available shortly for their eZ80. To date, linux > hasn't appeared on it. The eZ80 would likely run uClinux slowly for (a) > and (c). > > Personally, I can't think of any CPU that runs linux and maintains > binary compatibility with the Z180. > > A better project, IMHO, than uClinux on a Rabbit would a quality free C > compiler that targets the Rabbit. GCC, SDCC, or LCC would be places to > start. A good companion project would be a software emulator, ala MESS > or MAME. > > Kelly
Thanks to all who replied.