On 5 Dec 2009 at 0:23, Dave McGuire wrote:
On Dec 5, 2009, at 12:21 AM, Chuck Guzis wrote:
The emulation, while interesting, is sort of a
moot point nowadays,
as even a 75MHz P1 can run rings around a 5MHz V20 executing 8080
code via software emulation. And you can do more things with
software emulation than with the hardware emulation on a V20.
Troll alert. ;)
No troll. Just experience writing an emulator package that did both.
A software emulator can trap I/O and memory references and direct
them to a handler that allows one to emulate whatever hardware one
desires. The V20/V30/V33/V40/V50 simply map I/O accesses to
whatever port is present on the host machine--far less useful.
What's far more interesting to me on the V-series are the
instructions that one won't find on any Intel chip, such as the BCD
string arithmetic instructions.
--Chuck