Ersatz-11 emulates an entire PDP-11 system in software while
running on low-cost PC hardware. It outperforms all of the hardware
PDP-11 replacements on the market, outstripping them by a particularly
wide margin in disk-intensive applications. Hardware PDP-11 replacements
that use a Q-bus, Unibus, or ISA bus for I/O can't come close to
Ersatz-11's disk performance because they are limited to the speed of
the I/O bus for all disk transfers, regardless of actual disk (or disk
cache) speed. Ersatz-11 avoids this bottleneck since it uses the PC's
main memory and takes advantage of the tight disk-to-memory coupling in
modern PCs.
Ersatz-11 is by far the least expensive PDP-11 replacement product on
the market. It quickly pays for itself in reduced maintenance, power,
and climate control costs. Since its CPU is powered by the PC's
processor and not a special-purpose processor card, there's no expensive
custom hardware to maintain, and future upgrades to the PC's processor
will make its PDP-11 emulation even faster.
Commercial use is limited to 30-day evaluation.
-> URL: http://dbit.com/demo.html
Source: OS2.org
"The PDP-11 was a series of 16-bit minicomputers sold by Digital Equipment Corp. from 1970 into the 1990s, one of a succession of products in the PDP series. [1][2][2] The PDP-11 replaced the PDP-8 in many real-time applications,
although both product lines lived in parallel for more than 10 years.
The PDP 11 had several uniquely innovative features, and was easier to
program than its predecessors with its use of general registers. It was
replaced in the mid-range minicomputer niche by the VAX-11 32-bit extension of the PDP-11."