ModelSim仿真时注意事项，先添加信号，再仿真Run All，否则No Data

在仿真电路时，Run 一定time后，添加要观察的信号后，无论如何都没波形数据，出现No Data，原来是顺序问题（我的是这么回事）：

or1200仿真TB文件：

`timescale 1ns/100ps

module or1200_tb();

reg CLOCK_50;
reg rst;

initial begin
	CLOCK_50 = 1'b0;//时钟20ns一个周期，所以时钟频率是50MHZ
	forever #10 CLOCK_50 = ~CLOCK_50;
end

initial begin
	rst = 1'b1;//复位信号
	#200 rst = 1'b0;//在200ns处复位结束
	#1000 $stop;//仿真过程持续1000ns
end


or1200_top or1200_top_inst //openrisc最小系统，除了时钟、复位信号外，其余全部设置位0
(
	// System
	.clk_i(CLOCK_50), .rst_i(rst), .pic_ints_i(20'b0), .clmode_i(2'b00),

	// Instruction WISHBONE INTERFACE
	.iwb_clk_i(CLOCK_50), .iwb_rst_i(rst), .iwb_ack_i(1'b0), .iwb_err_i(1'b0), .iwb_rty_i(1'b0), .iwb_dat_i(32'b0),
	.iwb_cyc_o(), .iwb_adr_o(), .iwb_stb_o(), .iwb_we_o(), .iwb_sel_o(), .iwb_dat_o(),
`ifdef OR1200_WB_CAB
	.iwb_cab_o(),
`endif
`ifdef OR1200_WB_B3
	.iwb_cti_o(), .iwb_bte_o(),
`endif
	// Data WISHBONE INTERFACE
	.dwb_clk_i(CLOCK_50), .dwb_rst_i(rst), .dwb_ack_i(1'b0), .dwb_err_i(1'b0), .dwb_rty_i(1'b0), .dwb_dat_i(32'b0),
	.dwb_cyc_o(), .dwb_adr_o(), .dwb_stb_o(), .dwb_we_o(), .dwb_sel_o(), .dwb_dat_o(),
`ifdef OR1200_WB_CAB
	.dwb_cab_o(),
`endif
`ifdef OR1200_WB_B3
	.dwb_cti_o(), .dwb_bte_o(),
`endif

	// External Debug Interface
	.dbg_stall_i(1'b0), .dbg_ewt_i(1'b0), .dbg_lss_o(), .dbg_is_o(), .dbg_wp_o(), .dbg_bp_o(),
	.dbg_stb_i(1'b0), .dbg_we_i(1'b0), .dbg_adr_i(0), .dbg_dat_i(0), .dbg_dat_o(), .dbg_ack_o(),
	
`ifdef OR1200_BIST
	// RAM BIST
	.mbist_si_i(1'b0), .mbist_so_o(), .mbist_ctrl_i(0),
`endif
	// Power Management
	.pm_cpustall_i(1'b0),
	.pm_clksd_o(), .pm_dc_gate_o(), .pm_ic_gate_o(), .pm_dmmu_gate_o(), 
	.pm_immu_gate_o(), .pm_tt_gate_o(), .pm_cpu_gate_o(), .pm_wakeup_o(), .pm_lvolt_o(),
	.sig_tick()
);

endmodule

指令内存数据：

00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
a4000000
e020004d
e040004d
9c21000a
e0420800
15000001
00000000

指令共有6条

仿真结果：

继续看书~~~~~~