\chuck benz
Chuck Benz ASIC & FPGA Design
cbenz@chuckbenz.com
http://asics.chuckbenz.com
http://www.simadd.com
(603)465-3607

            sit-link

sit-link is a virtual serial link connecting two logic simulations,
whether local or geographically distant.

Serial data is passed between the simulations over a network
connection. By giving the virtual link a latency of several bit
times (for example, 40 to 200 bit times), the effect of real world
network latency can be minimized, and simulation performance of
typical complex designs will not degrade significantly.*

Using sit-link requires adding one simple module to the simulation
to represent one end of the serial link, with connections needed
only to the transmit and receive serial data. A separate application
is run on the same machine as the simulator to make the network
connection. sit-link is simple to integrate because data is passed
between the simulator and the application by unix named pipes, avoiding
the need for PLI/VPI/DPI. sit-link is easily added to existing testbenches.
If desired, PLI/VPI/DPI implementations of sit-link will be available.

sit-link allows inter-company simulations to be implemented without
exposing intellectual property. The simulation test bench on each
side of the link retains full control of the simulation, and can end
simulation when interoperability goals have been met, or upon any other
desired condition.

sit-link can be started discretely with each run of a simulation, or act
as a server that starts a simulation in response to a connection.

An optional sit-link proxy can serve as an intermediary and match pairs
of simulators, simplifying firewall port forwarding considerations.



*The two simulations will advance in simulation time together, so the
performance is necessarily limited by the slower of the two.