What are the really unusual or weird computers?

[Jim Battle]

Christian Corti wrote:
> On Fri, 22 Jun 2007, Sridhar Ayengar wrote:
>> How about the Timex TM100M?  It never got past the prototype-stage, 
>> but it executes BASIC in hardware.
> 
> Well, so does the Wang 2200.
> 
> Christian
> 

Not really -- the basic interpreter is written in microcode, but I 
wouldn't call that execution in hardware.

Also, I'd argue that the microcode is really nearly an ISA -- there are 
no pipeline hazards, the uword is very narrow (20b in the 2200A/B/C/S/T, 
23b in the VP/MVP).  The only thing that makes it ucode like is that 
some instruction formats have control fields to manipulate independent 
behaviors, and that jumps are within ucode page.  Long jumps take a bit 
of extra work.

The power of the first generation 2200 (A/B/C/S/T) was roughly the same 
as a 4 MHz Z80, I'd estimate.  The VP umachine was effectively about 
5x-8x faster, and it was a lot nicer to program too.  A factor of 2.7 
was due to a faster cycle time (1.6 us vs 600 ns per uinst); a factor of 
two was due to the 1st gen being a nibble machine, while the VP could do 
8b and 16b ops; the rest was a collection of other improvements.