quartue II 中关于跨模块task调用的错误解决

想练一下封装功能块的时候遇到了一个报错

`timescale 1ns/1ps

module minganxinhaoliebiao();
wire     clk,rst;//这里的值是在调用模块中产生的，所以是wire
reg    test1;
reg    a,b,c,d;
    
//调用层例化
sys_ctrl_task    sys_ctrl(
.clk            (clk),
.rst            (rst)
);


initial begin
    sys_ctrl.sys_rst(200);
    #1000;
    write;
end


endmodule


//************************************
//调用层
//***********************************
module sys_ctrl_task(clk,rst);
output    reg    clk;
output    reg    rst;

parameter    PERIOD = 20;        //时钟周期/ns    
parameter    RST_ING = 1'b0;    //有效复位值

initial begin
    clk = 0;
    forever
        #(PERIOD/2) clk = ~clk;    
end
//----------------------------------------
//任务封装
//-----------------------------------------
task    sys_rst;
    input    [31:0]    rst_time;
    begin
        rst = RST_ING;
        #rst_time;
        rst = ~RST_ING;
    end
endtask

endmodule

Error (10207): Verilog HDL error at minganxinhaoliebiao.v(16): can't resolve reference to object "sys_rst"
Error (12153): Can't elaborate top-level user hierarchy
但是我的sys_rst是定义的了啊，为什么还会报这种错