pmax section 4 documentation, inspired by PR#4527. Lots of typos,
misspellings, and grammatical errors corrected. A foolish consistency
(the hobgoblin of my small mind) in capitalization enforced for
certain trademarks (DECthis, DECthat, and so on). A little white
space added here and there for clarity. Some nroff peccadillos
tended to. Further remarks over issues not dealt with will be
committed in the PR.
from 16-bit device addresses to 32-bit TC DMA space.
* Sync with reality (pmax config now attaches ioasic at tc, not
vice-versa, for compatibility with the Alpha.)