NFS on BeagleBoard

I discovered last night that Moonfish on the BeagleBoard will export HardDisc0 via NFS so that it’s visible to Sunfish on the Iyonix. I used it to take a backup of HardDisc0 to NAS (i.e. both the BB and NAS were visible to the Iyonix, so it was just a case of drag and drop on the Iyonix from NFS to SMB).

Sunfish didn’t work on the BB, though.

Sunfish is another one that needs alignment exceptions turned off to work.

Interesting – I had already turned alignment exceptions off. I know I had, because SparkFS worked on zip files.

Having turned them off, how long does that setting last? Until reset, and to all applications?

I must go and research what these alignment exceptions are. From what I had understood, if misaligned accesses were attempted, the Cortex processor would treat the data differently from previous ARM versions, so even if the exceptions were turned off, the programme would malfunction anyway. It seems this isn’t so.

Having turned them off, how long does that setting last? Until reset, and to all applications?

Correct.

I must go and research what these alignment exceptions are. From what I had understood, if misaligned accesses were attempted, the Cortex processor would treat the data differently from previous ARM versions, so even if the exceptions were turned off, the programme would malfunction anyway. It seems this isn’t so.

For the techie explanation, there’s information on the wiki here (Unaligned LDR & unaligned STR). Generally speaking C programs that trigger alignment exceptions will malfunction if you turn the exceptions off, whereas assembler programs will be more hit-and-miss.