diff --git a/26_Seminar13/27_Microcontrollers/2_1_bits.c b/26_Seminar13/27_Microcontrollers/2_1_bits.c
index 5a34574..0dfc771 100644
--- a/26_Seminar13/27_Microcontrollers/2_1_bits.c
+++ b/26_Seminar13/27_Microcontrollers/2_1_bits.c
@@ -31,10 +31,10 @@ int set_some_bits(void *dest, unsigned int val)
 
 int main()
 {
-    float var = 0;
-    uint32_t a=4095;
-    uint32_t b=2000;
-    uint32_t c=4095;
+    float var = -0.1;
+    uint32_t a=4096;
+    uint32_t b=0x7fffffff;
+    uint32_t c=1<<(32-9);
     uint32_t d=0xffff;
     int status = 0;
     //~ scanf("%x%x%x%x", &a, &b, &c, &d); //a=4095, b=2000, c=4095, d=0xffff
@@ -45,10 +45,11 @@ int main()
     set_all_bits(&a);
     printf("set_all_bits a: %#X\n",a);
 
+    printf("vol = %f\n",var);
     status = reset_some_bits(&var, b);
-    printf("reset_some_bits %d %#X %f\n",status, a, var);
-    status = reset_some_bits( &var, c );
-    printf("reset_some_bits %d %#X %f\n",status, a, var);
+    printf("reset_some_bits %d %#X %f\n",status, b, var);
+    status = reset_some_bits( &var, ~c );
+    printf("reset_some_bits %d %#X %f\n",status, c, var);
     set_all_bits(&var);
     status = reset_some_bits(&var, d);
     printf("reset_some_bits %d %#X %f\n",status, a, var);
diff --git a/26_Seminar13/27_Microcontrollers/2_1_bits.exe b/26_Seminar13/27_Microcontrollers/2_1_bits.exe
new file mode 100644
index 0000000..f8eec35
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diff --git a/26_Seminar13/27_Microcontrollers/2_1_bits.o b/26_Seminar13/27_Microcontrollers/2_1_bits.o
new file mode 100644
index 0000000..0aad0d1
Binary files /dev/null and b/26_Seminar13/27_Microcontrollers/2_1_bits.o differ