archive: homework4 homework1

2025-04-14 13:14:52 +08:00
parent 83be5ac8da
commit cfaf068677
3 changed files with 35 additions and 7 deletions
@@ -0,0 +1,30 @@
+// test1.c
+// 通过定时器实现以0.5Hz的频率闪烁一个小灯
+#include "homework4.h"
+
+unsigned char cnt = 0; // log timer T0 overflow counts
+
+void test1()
+{
+    set_38_2LED();
+    TMOD = 0x01; // timer T0 mode 1, 16-bit timer
+    TH0  = 0XB8;
+    TL0  = 0X00;
+    TR0  = 1; // timer T0 run
+    while (1) {
+        if (TF0 == 1) { // timer T0 overflow
+            TF0 = 0;    // clear timer T0 overflow flag
+            TH0 = 0xB8; // reload timer T0 value
+            TL0 = 0x00;
+            cnt++; // log timer T0 overflow counts
+            if (cnt >= 50) {
+                cnt   = 0;      // clear log timer T0 overflow counts
+                BUS1A = ~BUS1A; // toggle LED
+            }
+        }
+    }
+}
+void main()
+{
+    test1();
+}