Need to Use Variable in Assertions ## Delay

In reply to tirumalrao_m:
Try the following code: http://systemverilog.us/m_roseB.sv
You don’t need uvm; I just used it for the messaging. You can use $error.


module m_rose; 
	bit clk, a, b; 
	bit[3:0] delay=6; 
	int cycle=0;
	let VACUOUSOFF = 11; // assertion control type
	initial begin 
		$assertpasson(0); 
		$assertcontrol( VACUOUSOFF); //
	end
	always  @(posedge clk)  cycle <= cycle +1'b1; 
	
	default clocking @(posedge clk); endclocking
	initial forever #10 clk=!clk;   
	// I want to check b rose 6 cycle after a raises, 
        // and during 6 cycle b should be zero, should not toggle. 
    property p_delay; 
     int v; 
     ($rose(a), v=delay+1'b1, $display("Cycle=%d, START, time=%t, DELAY= %d", cycle, $time, delay)) |-> 
      (v>0 && !b, v=v-1'b1)[*0:$] ##1 v==0 ##0 $rose(b);
    endproperty 
	ap_delay: assert property(p_delay) $display("Cycle=%d, PASS", $sampled(cycle));   
			else  $display("Cycle=%d, FAIL", $sampled(c

Ben Cohen
http://www.systemverilog.us/ ben@systemverilog.us

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