<Can you restrict an architecture like this? I've never heard of an
<Interlectual Property case being based on the fact that the 2 products
<(CPUs) run the same instruction set.
DEC and oh I forget on PDP-8, NEC and intel on 8086/V20 and plenty more.
<Also, be warned that if you're going to use FPGAs you have to use the
<manufacturer's tools which are not going to be Open-Source, and which are
<not going to run under Open-Source OSes. Several of us have moaned about
Not all are restricted to one vendor. Just why bother.
Now, if you really want to build a PDP-11 of any kind yank the t11 chip
from a dead Vt240/241/RQDXn and build one to suit ones self. It's a real
PDP-11 and it does run RT11 (assuming standard devices) as the falcon card
does. If 64kb of addressing is not enough try building a mapper like most
of the 11s have, a couple of 74189s should do. This is a nice 40 pin dip
and not much hard to design with than z80 though the z80 never offered
things like selectable 8/16bit bus or selectable start/restart addresses
not to mention cycle and clock options. Performance is better than LSI-11
if memory runs without wait states.
Creating the chip is half the task, putting it to work is the real fun.
Allison
Received on Thu Aug 26 1999 - 18:20:00 BST