= D =
Dread Questionmark Disease
dread high-bit disease n.
A condition endemic to some
now-obsolete computers and peripherals (including ASR-33 teletypes
and PRIME minicomputers) that results in all characters having
their high (0x80) bit forced on. This of course makes transporting
files to other systems much more difficult, not to mention the
problems these machines have talking with true 8-bit devices.
This term was originally used specifically of PRIME (a.k.a. PR1ME)
minicomputers. Folklore has it that PRIME adopted the reversed-8-bit
convention in order to save 25 cents per serial line per machine;
PRIME old-timers, on the other hand, claim they inherited the
disease from Honeywell via customer NASA's compatibility
requirements and struggled heroically to cure it. Whoever was
responsible, this probably qualifies as one of the most
cretinous design tradeoffs ever made. See meta bit.
--The Jargon File version 4.3.1, ed. ESR, autonoded by rescdsk.