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The below assertions check that gnt is not high for consecutive clk cycles. Q1: v1 vs. v2: Are there benefits or relevant differences between these styles. Q2: v2 vs. v3: Does the placement of delay matter? Besides for end of simulation termination. The questions are mainly about whether some style is better for the simulator, or there is some non-obvious situation I should consider. module top; bit clk, gnt; bit [19:0] gnt_a; initial begin gnt_a = 20'b0011001010_0000001101; #200 $finish; end assign gnt = gnt_a[19]; always clk = #5 ~clk; always@(posedge clk) begin gnt_a = gnt_a<<1; $display($time," gnt: %1b",gnt); end as_v1 : assert property ( @(posedge clk) not strong(gnt[*2]) ); as_v2 : assert property ( @(posedge clk) gnt |-> ##1 !gnt ); as_v3 : assert property ( @(posedge clk) gnt ##1 1'b1 |-> !gnt ); endmodule Code is also available here: https://edaplayground.com/x/4GXn

Hello all, This is very basic question and I know its not possible, but still I need to put some delay or wait in start of simulation/end of elaboration. I will give you the background, In end of elaboration i an initializing the value to a pin, and that pin is quite required for reset vector address. In start of simulation I am opening my gdb, which which stop at my reset vector address, but it seems the gdb is not updating the reset vector value, so I need a small delay. Is it possible? Any suggestion will be very helpful :) Thanks and Regards, Nitin_s

Hi all, is there any way to implement the intra assignment delay in systemC without using sc_event()? for example : in verilog we write out = #10 in1 + in2; // intra assignment delay. how would i implement the same in systemC? regards, jatin

Hello, I need to port following code from Verilog to SystemC: assign #DELAY out = in; What is the best known method to do this in SystemC? Similar question on stackoverlow https://stackoverflow.com/questions/5566785/specifying-signal-delays-in-systemc-as-clause-after-in-vhdl

Good day, I have a question regarding how to determine the appropriate delay value for the wait( ) function call. In the target b_transport callback, we can add delay to the simulation time by passing delay amount to the wait( ) function. In simulation that uses quantum and temporal decoupling that targets super fast instruction accurate simulation, the timing does not have to be very detail (loosely timed). With or without delay in the target callback function will not cause any functional inaccuracy and still we could produce the platform that can support firmware/software development. Still if we want to put a delay to the wait( ), how can we determine the appropriate delay value for the function parameter? Thank you. Regards, Arya.

I've run into the following issue using the built-in UVM register tests. The built-in UVM register tests (seem to) start R/W-ing immediately after top-level reset is released. This was fine, initially. See attached image "Capture". We now have some delay between the release of top-level reset and the actual reset going to the register block. This is resulting in a read occurring before reset to the rtl regblock is released, and causes the test to hang. See attached image "Capture2". Without modifying the built-in register tests/sequences, how would anyone suggest that we cleanly delay the stimulus? Perhaps I just need to make the stimulus aware of the different reset when the model/stimulus is generated, or simple add some delay to a phase before the R/W-ing starts. (The former sounds right. If that's the solution, I'll need to figure out how we're generating the model/stimulus.) I've just started hunting around for the built-in UVM register test sequences and will return to it tomorrow, but will anyone tip me off as to what names I should be searching for? thanks This has been useful, https://verificationacademy.com/cookbook/registers/builtinsequences, but it seems I need to do some more reading and hunting before I grasp how the built-in register stimulus is created and used.

Hi all, i am trying to translate a simulink model to system c module. The simulink block is a source block where it generates random number in the range of [ 0 , 253 ] and with a explicit sample period( the block produces outputs and if appropriate, updates its internal state) of 9 ns, and the output of this block is given to the next block with a latency of 1 sample period. i tried to translate this block to a system c module as shown below: #include "systemc.h" #include <stdlib.h> //for srand(uint) and rand() SC_MODULE(RNG){ sc_in_clk clk; sc_out< sc_uint > output; sc_uint A; void process(){ // while(true) { wait(9, SC_NS); // Timed sampling, based on simulink block sample time A=rand() % 254 ; // do the process wait(9, SC_NS); // delaying the output for 1 latency ie. 1 sample period output.write(A); // then write the output } } SC_CTOR(RNG) { SC_THREAD(process); sensitive<< clk.pos(); } will the above code imitates the simulink model with its specifications as i prescribed? please have a look and let me know how i can proceed for the solution. Thank you.

Hi All, while simulating A2D convertor, I got following problems. Compilation: No Error running .exe file returns the following error message: ----------------------------------------------------------------------------------------------------------------------------------------------------------------- Warning: SystemC-AMS: Initialization for tracing of: CLK failed set wave to 0 In file: sca_trace_object_data.cpp:136 In process: method_p_0 @ 0 s Error: SystemC-AMS: Sample id (0) is greater than delay (0 while initializing port: A2D_dut.a2d.eoc In file: /home/4all/packages/systemc/2.2.0-sl4.5//include/scams/predefined_moc/tdf/sca_tdf_sc_out.h:418 In process: A2D_dut.a2d.sca_implementation_0.cluster_process_0 @ 0 s ----------------------------------------------------------------------------------------------------------------------------------------------------------------- In this regards, I have checked the complete code as well as the the files suggested in error message (/sca_tdf_sc_out.h:418), (sca_trace_object_data.cpp:136), but I did not get any clue. my codes look like this: //A2D.h SCA_TDF_MODULE (a2d_nbit) { //port declaration sca_tdf::sca_in<double> a_in; // analog input pin sca_tdf::sca_de::sca_in<sc_dt::sc_logic> start; //start signal sca_tdf::sca_de::sca_in<bool> clk; //clock signal sca_tdf::sca_de::sca_out<sc_dt::sc_logic> eoc; //end of conversion pin sca_tdf::sca_de::sca_out<sc_dt::sc_lv<8> > d_out; // digital output signal a2d_nbit(sc_core::sc_module_name nm, double Vmax_ = 5.0, double delay_ = 10.0e-3, int bit_rng = 8): a_in("a_in"), start("start"),clk("clk"), eoc("eoc"), d_out("d_out"), Vmax(Vmax_), delay(delay_), bit_range(bit_rng){} void set_attribute() { set_timestep(1, sc_core::SC_MS); eoc.set_delay(0); } void initialize() { eoc.initialize(sc_dt::SC_LOGIC_0); start.initialize(sc_dt::SC_LOGIC_0); } void processing(); private: double Vmax; // ADC maximum range double delay; // ADC conversion time int bit_range; //vector length of d_temp and d_out }; //A2D_top_level.h SC_MODULE (A2D_top_level) { a2d_nbit a2d; vtg_src input_vtg; sc_core::sc_clock clk1; void start_logic(){ while(true) { start.write(sc_dt::SC_LOGIC_0); wait(20, sc_core::SC_MS); start.write(sc_dt::SC_LOGIC_1); wait(20, sc_core::SC_MS); start.write(sc_dt::SC_LOGIC_0); sc_core::sc_stop(); } } SC_CTOR(A2D_top_level) : in("in"), out("out"), a2d("a2d"), input_vtg("input_vtg"),clk1("clk1",10, 0.5, true), start("start"), eoc("eoc") { input_vtg.out(in); a2d.a_in(in); a2d.start(start); a2d.clk(clk1.signal()); a2d.eoc(eoc); a2d.d_out(out); SC_THREAD(start_logic); } public: sca_tdf::sca_signal <double> in; sc_core::sc_signal<sc_dt::sc_lv<8> > out; sc_core::sc_signal<sc_dt::sc_logic> start; sc_core::sc_signal<sc_dt::sc_logic> eoc; }; //A2D_test.cpp int sc_main(int argc, char* argv[]) { A2D_top_level A2D_dut("A2D_dut"); sca_util :: sca_trace_file* atfs = sca_util :: sca_create_tabular_trace_file("A2D.dat"); sca_util :: sca_trace(atfs, A2D_dut.a2d.clk, "CLK"); sca_util :: sca_trace(atfs, A2D_dut.start, "START"); sca_util :: sca_trace(atfs, A2D_dut.in, "INPUT"); sca_util :: sca_trace(atfs, A2D_dut.out, "OUTPUT"); sca_util :: sca_trace(atfs, A2D_dut.eoc, "EOC"); sc_start(1.5, SC_SEC); sca_util :: sca_close_tabular_trace_file (atfs); return 0; } could you please help in solving this problem.... regards, Milind