Add Led_blinker example

examples/Led_blinker/Led_blinker.sv

@@ -0,0 +1,94 @@
+module Led_blinker
+  (
+   i_clock,
+   i_enable,
+   i_switch_1,
+   i_switch_2,
+   o_led_drive
+   );
+
+    input i_clock;
+    input i_enable;
+    input i_switch_1;
+    input i_switch_2;
+    output o_led_drive;
+
+    parameter c_CNT_100HZ = 125;
+    parameter c_CNT_50HZ  = 250;
+    parameter c_CNT_10HZ  = 1250;
+    parameter c_CNT_1HZ   = 12500;
+
+    reg [31:0] r_CNT_100HZ = 0;
+    reg [31:0] r_CNT_50HZ = 0;
+    reg [31:0] r_CNT_10HZ = 0;
+    reg [31:0] r_CNT_1HZ = 0;
+
+    reg        r_TOGGLE_100HZ = 1'b0;
+    reg        r_TOGGLE_50HZ  = 1'b0;
+    reg        r_TOGGLE_10HZ  = 1'b0;
+    reg        r_TOGGLE_1HZ   = 1'b0;
+
+    reg        r_LED_SELECT;
+    //wire       w_LED_SELECT;
+
+
+
+    always @(posedge i_clock) 
+    begin
+        if (c_CNT_100HZ == c_CNT_100HZ - 1)
+            begin
+                r_TOGGLE_100HZ <= !r_TOGGLE_100HZ;
+                r_TOGGLE_100HZ <= 0;
+            end
+        else
+            r_CNT_100HZ <= r_CNT_100HZ + 1;
+    end
+
+    always @(posedge i_clock) 
+    begin
+        if (c_CNT_50HZ == c_CNT_50HZ - 1)
+            begin
+                r_TOGGLE_50HZ <= !r_TOGGLE_50HZ;
+                r_TOGGLE_50HZ <= 0;
+            end
+        else
+            r_CNT_50HZ <= r_CNT_50HZ + 1;
+    end
+
+    always @(posedge i_clock) 
+    begin
+        if (c_CNT_10HZ == c_CNT_10HZ - 1)
+            begin
+                r_TOGGLE_10HZ <= !r_TOGGLE_10HZ;
+                r_TOGGLE_10HZ <= 0;
+            end
+        else
+            r_CNT_10HZ <= r_CNT_10HZ + 1;
+    end
+
+    always @(posedge i_clock) 
+    begin
+        if (c_CNT_1HZ == c_CNT_1HZ - 1)
+            begin
+                r_TOGGLE_1HZ <= !r_TOGGLE_1HZ;
+                r_TOGGLE_1HZ <= 0;
+            end
+        else
+            r_CNT_1HZ <= r_CNT_1HZ + 1;
+    end
+
+    always @(*) begin
+        case ({i_switch_1, i_switch_2})
+            /* verilator lint_off COMBDLY */
+            2'b11 : r_LED_SELECT <= r_TOGGLE_1HZ;
+            2'b10 : r_LED_SELECT <= r_TOGGLE_10HZ;
+            2'b01 : r_LED_SELECT <= r_TOGGLE_50HZ;
+            2'b00 : r_LED_SELECT <= r_TOGGLE_100HZ;
+            /* verilator lint_on COMBDLY */
+        endcase
+    end
+
+    assign o_led_drive = r_LED_SELECT & i_enable;
+
+
+endmodule

examples/Led_blinker/makefile

@@ -0,0 +1,6 @@
+VERILATOR_ROOT := ../..
+PROJECT_NAME := Led_blinker
+SOURCES := *.sv
+SIMFILES := *.cpp
+
+include $(VERILATOR_ROOT)/verilator.mk

examples/Led_blinker/sim.cpp

@@ -0,0 +1,28 @@
+#include "VLed_blinker.h"
+#include "verilated.h"
+
+#include <cassert>
+#include <vector>
+#include <iostream>
+
+int main(int argc, char** argv) {
+    VLed_blinker* top = new VLed_blinker;
+    Verilated::commandArgs(argc, argv);
+
+    int stimuli_a[] = { 2, -1, 1, -6 };
+    int stimuli_b[] = { 4,  5, 2,  7 }; 
+
+    for (int i = 0; i < sizeof(stimuli_a) / sizeof(stimuli_a[0]); i++) {
+        if (Verilated::gotFinish()) break;
+
+        top->a = stimuli_a[i];
+        top->b = stimuli_b[i];
+
+        top->eval();
+
+        assert(top->c == (stimuli_a[i] + stimuli_b[i]));
+    }
+
+    delete top;
+    return 0;
+}