Further samos work

I'm off for 8 days of holiday but this should give me a bit of time (night train!) to work on some of the OS so that when i return hopefully I can simulate a simple PowerPC board with a single RS232 device for input and output.

So far only the RS232 device driver supports the proper architecture I'm going to use but then the only other driver I have is an RTC at the moment.

Once that, dynamic memory and the new Process Thread management code is in the API between applications and the Operating System can have some work done.

Initially the idea was to use newlib and that will still be the case. The difference is that there will be a few extra calls for device drivers so that application layer code will be able to perform reads and writes.

I have some degree of confidence that the above can be done during my Ski trip. The goal is that from here I can port the PowerPC stuff over to ARM7 or something and get a cheap eval board to get it all up and running - hopefully much like PSIM (PowerPC Simulator) has been integrated into GDB there will also be an ARM version.