Tutorial¶
This tutorial focuses on hierarchical physical restructuring using spydrnet-physical plugin.
If you are starting with a spydrnet project and looking for complete detail
of the data structure and base classes of SpyDrNet please refer
byuccl/SpyDrNet Documentation.
This tutorial focuses mainly on reading the existing Verilog netlist in spydrnet
project and performing a series of netlist manipulation (which are correct by construction) to
achieve the intended netlist structure.
Note
SpyDeNet focuses only on restructural Verilog netlist, netlists containing always and initial blocks are not valid structure netlists.
Example¶
The following example shows how you can perform a netlist manipulation. In this example, we are going to generate feedthrough for a single wire connected between in0 input port and in1 port of instance inst_1__1. The cable/net name of this connection is wire0, which is obtained from the the Verilog netlist basic_hierarchy (wire name is not annotated in the following schematic).
from os import path
import spydrnet as sdn
import spydrnet_physical as sdnphy
netlist = sdnphy.load_netlist_by_name('basic_hierarchy')
# Read example netlist
top = netlist.top_instance.reference
# get instance of wire0 and inst_2_0
cable0 = next(top.get_cables("wire0"))
inst2 = next(top.get_instances("inst_1_0"))
top.create_feedthrough(inst2, cable0)
# Add dummy unconnected wire
top.create_unconn_wires()
sdn.compose(netlist, '_output_wire.v', skip_constraints=True)
Output¶
For more detail of spydrnet-physical features and examples, please check examples section
Shell Interface¶
SpyDrNet-Physical allows you to load a shell-like interface after
to perform live modifications and debugging of the Script.
A shell like interactive interface can be involked by running sdnphy command
which opens interactive shell enviroment as shown below.
bash>>> sdnphy
___ ___ _ _ _ ___ _ _ _
/ __|_ __ _ _| \ _ _| \| |___| |_ ___| _ \ |_ _ _ __(_)__ __ _| |
\__ \ '_ \ || | |) | '_| .` / -_) _|___| _/ ' \ || (_-< / _/ _` | |
|___/ .__/\_, |___/|_| |_|\_\___|\__| |_| |_||_\_, /__/_\__\__,_|_|
|_| |__/ |__/
Launching SpyDrNet-Physical interactive mode
spydrnet >>>
In-script debugging¶
A shell-like interface can also be invoked from the python script. Use the following command to import shell and launch.
from spydrnet_physical.utils.shell import launch_shell
#
# script before launching the shell
#
launch_shell()
#
# script after exiting the shell
#
For more information related to shell interface and shortcuts, please read sdnphy Shell section.
Visualization¶
Spydrnet-physical also provides a basic hierarchical visualizer based on project project Nic30/d3-hwschematic. The following example script can be used to export an HTML file to visualize live on the web browser.
import spydrnet_physical as sdnphy
from spydrnet_physical.composers.html.composer import HTMLComposer
netlist = sdnphy.load_netlist_by_name('basic_hierarchy')
composer = HTMLComposer()
composer.run(netlist, file_out="_initial_design.html")
Note
Due to the Cross-Origin Resource Sharing policy, the HTML page can not be embedded on this page. To visualize the netlist, please click on the following link.