SystemVerilog assertion

Question

I have the following interfaces:

interface tx_in_interface (input bit clk, input bit tx_srstn);
   //dut input
   logic [15:0] xi;   
   logic [15:0] xq;   
   logic [15:0] sin;  
   logic [15:0] cos;  
   int  chind2;   
endinterface



interface tx_out_interface (input bit clk, input bit tx_srstn);
   //dut output
   logic [15:0] y;
   int chind2;   
endinterface

I want to check that every time sin equal to 1(dec) y will be xi/sqrt(2), and every time cos equal to 1(dec) y will be xq/sqrt(2).

Can I do it with a specific kind of systemVerilog assertion (with no use of scoreboard or coverage)?

Answer 1

Yes I think you can simple write the following 2 properties.

property sin_check;
  (sin == 'd1) |-> y == (xi/sqrt(2));
endproperty

property cos_check;
  (cos == 'd1) |-> y == (xq/sqrt(2));
endproperty

Answer 2

Following 2 assertions can verify your specified condition:

//Creating instances of interface 
tx_in_interface tx_i; 
tx_out_interface tx_o;

//Checking conditions 
assert property (@posedge tx_i.clk) (tx_i.sin == 1) |-> tx_o.y == (tx_i.xi/sqrt(2)); 
else $error("Sine output error!");

assert property (@posedge tx_o.clk) (tx_i.cos == 1) |-> tx_o.y == (xq/sqrt(2)); 
else $error("Cos output error!");

SystemVerilog Assertions Tutorial by Duolos is an excellent resource.