Xcelium Mixed Signal: Co-Simulation Functionalities

As part of the application-centric enhancements in the Xcelium mixed-signal verification, a set of related SystemVerilog and SPICE co-simulation use cases can be now enabled using a single xrun/xmelab command-line option, -dms_cosim.

If you are running co-simulations for your design or verification, you can use the -dms_cosim option to automatically enable the following technologies for a more optimized and out-of-box experience with mixed-signal designs:

Automatically process Out-Of-Module References to SPICE (-autospiceoomr)
Optimize analog connectivity across digital/SV blocks using discipline resolution optimization (-amsdropt) while shutting off the more comprehensive discipline resolution algorithm from Verilog-AMS standard (-disres none)
Enable advanced SystemVerilog and mixed-signal connectivity improvements such as connecting SystemVerilog Hierarchical UDT to electrical, SystemVerilog interface to DMS/Verilog-AMS signals, SystemVerilog multi-dimensional array to SPICE/electrical ports, coercion for SystemVerilog interfaces/program/checker blocks, using wildcard-named port connections in SV bind statements (all using one option -sv_ms).

The following is an example of a design where discipline resolution is enabled (-disres none is disabled) because the design has mixed signal content that requires more comprehensive mixed-signal elaboration.

command: top.sv -64 amscf.scs -timescale 1ns/100ps -dms_cosim child.vams
============top.sv=============
module top;
wire [0:2]foo ;
spice_driver spice_drvr0 (foo); //SPICE DRVR
dig_receiver dig_rcvr0(foo);
endmodule
module dig_receiver(input wire [0:2]in);
spice_dut rcvr0 (in);//SPICE DUT
endmodule
module spice_driver (output wire [0:2] out);//DIGITAL VERSION OF spice_driver
endmodule
module spice_dut(input wire [0:2] in);//DIGITAL VERSION of spice_dut
endmodule

============child.vams==========
`include "disciplines.vams"
module child();
electrical a;
endmodule

============amscf.scs===========
include "./ana_gate.sp"
amsd {
portmap subckt=spice_driver autobus=yes file="./spice_driver.pb"
config cell=spice_driver use=spice
portmap subckt=spice_dut autobus=yes file="./spice_dut.pb"
config cell=spice_dut use=spice
ie vsup = 5.0
}
============ana_gate.sp==========
simulator lang=spice
.subckt spice_dut in_0 in_1 in_2
.ends
.subckt spice_driver out[0] out[1] out[2]
.ends
=============================

All such designs consisting of .vams, .vhams, or .svams, are considered as a co-simulation application and the following DISCOS warning is displayed:

xmelab: *W,DISCOS: [DMSINFO] '-disres none' which is one of the automated -dms_cosim optimizations is disabled for this design because the design has mixed signal content which requires more comprehensive mixed-signal elaboration.

The following is an example of how using the -dms_cosim option optimizes mixed-signal elaboration algorithms for AMS co-simulation applications (SV+SPICE). Auto-detected co-sim design, switching elaboration to co-simulation(-disres none and -amsdropt) mode.

command: xrun top.sv -64 amscf.scs -timescale 1ns/100ps -dms_cosim
================top.sv================
module top;
wire [0:1][0:2]foo ;
spice_driver spice_drvr0 (foo[0]); //SPICE DRVR
spice_driver spice_drvr1 (foo[1]); //SPICE DRVR
dig_receiver dig_rcvr0(foo);
endmodule
module dig_receiver(input wire [0:1][0:2]in);
spice_dut rcvr0 (in[0]);//SPICE DUT
spice_dut rcvr1 (in[1]);//SPICE DUT
endmodule
module spice_driver (output wire [0:2] out);//DIGITAL VERSION OF spice_driver
endmodule
module spice_dut(input wire [0:2] in);//DIGITAL VERSION of spice_dut
endmodule
================amscf.scs==============
include "./ana_gate.sp"
amsd {
portmap subckt=spice_driver autobus=yes file="./spice_driver.pb"
config cell=spice_driver use=spice
portmap subckt=spice_dut autobus=yes file="./spice_dut.pb"
config cell=spice_dut use=spice
ie vsup = 5.0
}
============ana_gate.sp=================
simulator lang=spice
.subckt spice_dut in_0 in_1 in_2
.ends
.subckt spice_driver out[0] out[1] out[2]
.ends
==============================

Xcelium Mixed Signal: Co-Simulation Functionalities

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