> Sure, but channel controllers and PPUs are very different beasts. You can’t > run your OS on a channel controller, which is exactly what Cray did on the > 6600. Nor can you implement the entire operator user interface on a channel > controller, as was done in the DSD PPU program.
Yes, I realize that a CDC PPU is a very versatile I/O processor, compared to channel controllers from other vendors, but the PPU idea pretty much stayed with CDC and nobody else. It fails the "novel features in the 6600 that were widely adopted by other machines" test. -- Will
