3 files changed, 5 insertions, 6 deletions
diff --git a/nandgame/cpp/Vcomputer__main.cpp b/nandgame/cpp/Vcomputer__main.cpp
index cc0f7c0..6908377 100644
--- a/nandgame/cpp/Vcomputer__main.cpp
+++ b/nandgame/cpp/Vcomputer__main.cpp
@@ -31,7 +31,7 @@ int main(int argc, char **argv, char **) {
     fprintf(stderr, "Usage: %.20s [filename]\n\n", argv[0]);
     exit(-1);
   }
-  int i = 0;
+
   puts("Start simulation.");
   // topp->computer->clk_in = 0;
   topp->clk_in = 0;
@@ -53,9 +53,8 @@ int main(int argc, char **argv, char **) {
 
   simpc_ui_init();
 
-  while (VL_LIKELY(!contextp->gotFinish()) && i < 500) {
-    // doesn't work.
-    // topp->computer->clk_in = ~topp->computer->clk_in;
+  while (VL_LIKELY(!contextp->gotFinish()) && contextp->time() < 500) {
+    auto i = contextp->time();
 
     if (i != 0 && (i % TICKS_PER_INS) == 0) {
       topp->clk_in = !topp->clk_in;
diff --git a/nandgame/cpp/simpc_ui.cpp b/nandgame/cpp/simpc_ui.cpp
index 35cbdcb..eead4b5 100644
--- a/nandgame/cpp/simpc_ui.cpp
+++ b/nandgame/cpp/simpc_ui.cpp
@@ -44,7 +44,7 @@
 
 bool paused = false;
 
-void simpc_ui_write(const std::unique_ptr<Vcomputer> &topp, int &i,
+void simpc_ui_write(const std::unique_ptr<Vcomputer> &topp, uint64_t &i,
                     StepPosition_t sp) {
   uint16_t opcode = topp->computer->PC_content_int;
 
diff --git a/nandgame/cpp/simpc_ui.h b/nandgame/cpp/simpc_ui.h
index 4a990a6..71b651f 100644
--- a/nandgame/cpp/simpc_ui.h
+++ b/nandgame/cpp/simpc_ui.h
@@ -6,7 +6,7 @@
 #include <memory>
 
 void simpc_ui_init(void);
-void simpc_ui_write(const std::unique_ptr<Vcomputer> &topp, int &i,
+void simpc_ui_write(const std::unique_ptr<Vcomputer> &topp, uint64_t &i,
                     StepPosition_t sp);
 void simpc_ui_finish_message(const std::unique_ptr<VerilatedContext> &contextp,
                              const std::unique_ptr<Vcomputer> &topp);