diff --git a/src/debugger.c b/src/debugger.c
index 0b2dc9c..e0bfbc4 100644
--- a/src/debugger.c
+++ b/src/debugger.c
@@ -77,7 +77,7 @@
 #define EXEC_BKPT 1
 
 int enter_debugger = 0;
-int in_debugger = 0;
+bool in_debugger = false;
 int exec_flags = 0;
 
 static int continue_flag;
@@ -3990,7 +3990,7 @@ static void cmd_step( int argc, char** argv )
     if ( n <= 0 )
         return;
 
-    in_debugger = 1;
+    in_debugger = true;
     step_instruction();
 
     if ( exec_flags & EXEC_BKPT ) {
@@ -4196,16 +4196,16 @@ int debug( void )
         } else {
             printf( "Undefined command \"%s\". Try \"help\".\n", argv[ 0 ] );
         }
-        in_debugger = 0;
+        in_debugger = false;
 
     } while ( !continue_flag );
 
     /*
      * adjust the hp48's timers
      */
-    in_debugger = 1;
+    in_debugger = true;
     ticks = get_t1_t2();
-    in_debugger = 0;
+    in_debugger = false;
 
     if ( saturn.t2_ctrl & 0x01 ) {
         saturn.timer2 = ticks.t2_ticks;
diff --git a/src/debugger.h b/src/debugger.h
index 411eeff..c2f257f 100644
--- a/src/debugger.h
+++ b/src/debugger.h
@@ -11,7 +11,7 @@
 #define CLASS_MNEMONICS 1
 
 extern int enter_debugger;
-extern int in_debugger;
+extern bool in_debugger;
 extern int exec_flags;
 
 /**************/
diff --git a/src/emu_actions.c b/src/emu_actions.c
index 1261835..cf97914 100644
--- a/src/emu_actions.c
+++ b/src/emu_actions.c
@@ -293,7 +293,7 @@ void do_shutdown( void )
         saturn.int_pending = false;
     }
 
-    int wake = ( in_debugger ) ? 1 : 0;
+    bool wake = in_debugger;
     t1_t2_ticks ticks;
 
     do {
@@ -314,14 +314,14 @@ void do_shutdown( void )
             interrupt_called = 0;
             ui_get_event();
             if ( interrupt_called )
-                wake = 1;
+                wake = true;
 
             if ( saturn.timer2 <= 0 ) {
                 if ( saturn.t2_ctrl & 0x04 )
-                    wake = 1;
+                    wake = true;
 
                 if ( saturn.t2_ctrl & 0x02 ) {
-                    wake = 1;
+                    wake = true;
                     saturn.t2_ctrl |= 0x08;
                     do_interupt();
                 }
@@ -330,26 +330,26 @@ void do_shutdown( void )
             if ( saturn.timer1 <= 0 ) {
                 saturn.timer1 &= 0x0f;
                 if ( saturn.t1_ctrl & 0x04 )
-                    wake = 1;
+                    wake = true;
 
                 if ( saturn.t1_ctrl & 0x03 ) {
-                    wake = 1;
+                    wake = true;
                     saturn.t1_ctrl |= 0x08;
                     do_interupt();
                 }
             }
 
-            if ( wake == 0 ) {
+            if ( !wake ) {
                 interrupt_called = 0;
                 receive_char();
                 if ( interrupt_called )
-                    wake = 1;
+                    wake = true;
             }
         }
 
         if ( enter_debugger )
-            wake = 1;
-    } while ( wake == 0 );
+            wake = true;
+    } while ( !wake );
 
     stop_timer( IDLE_TIMER );
     start_timer( RUN_TIMER );