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Beside this dedicated processors the problem with multiple 
processors on bus coupled systems is, that adding more 
and more processors on the same bus, does not linear 
increase the performance. From a number of 4 to 6 
processors on the same bus the performance decreases. 
This can be avoided by using bus-less processors like 
transputers. The currently available INMOS T800 chips (see 
Fig. 3) give a performance of 1.5 Mflops/10 Mips each. 
Figure 3: The INMOS T800 Transputer Chip 
They can be configured in any number and topology being 
appropriate for the application. Communication is done via 
so called links, giving a net point to point transfer rate of 
1.8 Mbyte/sec for each link. Arrays of transputers forming 
so called computing clusters can be build in topologies by 
using software controllable network configuration units. 
They may be used either as an add-on's on standard 
graphic workstations or as stand alone systems with 64 
up to 256 transputers. A configuration of 64 T800 super 
computing cluster has a performance of 640 Mips and 96 
Mflops at a price of approximately 250.000 $. Parellel 
compilers of nearly all high level computer languages, like 
C, FORTRAN, PASCAL and PROLOG are available as a 
variety of software development tools. Today programming 
of such arrays seems to be rather a tedious job in 
comparision to programming standard processors. In addition 
the latest processor developments like CISC (MC 68040) 
show a performance that comes close to the requirements 
in this application area.