Re: more serial ports for rabbit3000

There's no easy answer to your questions. 

We are moving to the RCM6750 for twice the memory, 4-times the speed,
and the smaller size. It doesn't have the I/O of the R3k series, but
with the addition of a CPLD/FPGA you can add more I/O than you will 
ever need. That is what we did. We interface to the CPLD/FPGA via 
SPI, which is very fast on the R6k. Drop some UARTS in the CPLD/FPGA 
and you're off.

My understanding of Rabbit development from conversations with some
Rabbit people pre-Digi buy-out is that, the R6000 is the end of the
8-bit Rabbit line. That they were working on coming out with a 32-bit
Rabbit. They were considering using something like a MIPS as the 
basic core and making some mods to it, much like they did with the 
Z80 to create the Rabbit. I don't know if that's still in the plans. 
I get a lot less info from the Rabbit people now that they are Digi. 
And they don't show up at the Embedded Systems conferences anymore.

I like the PIC line of microcontrollers, so I bought a PIC32 dev kit
to play with. What a nightmare! I've never had such difficulty getting
it to work, especially Ethernet. After some months of struggling with 
it, I shelved it. The Netburner is a much better and easier platform 
to use if you need 32-bit support. But it's physically much larger. 
If you can stand the extra size, and want 32-bits, I think Netburner 
is a better way to go. 

Steve