完成第一次实验

labcodes_answer/lab1_result/kern/driver/clock.c

@@ -33,8 +33,8 @@ void
 clock_init(void) {
     // set 8253 timer-chip
     outb(TIMER_MODE, TIMER_SEL0 | TIMER_RATEGEN | TIMER_16BIT);
-    outb(IO_TIMER1, TIMER_DIV(100) % 256);
-    outb(IO_TIMER1, TIMER_DIV(100) / 256);
+    outb(IO_TIMER1, TIMER_DIV(1000) % 256);
+    outb(IO_TIMER1, TIMER_DIV(1000) / 256);
 
     // initialize time counter 'ticks' to zero
     ticks = 0;

labcodes_answer/lab1_result/kern/trap/trap.c

@@ -149,7 +149,12 @@ struct trapframe switchk2u, *switchu2k;
 /* trap_dispatch - dispatch based on what type of trap occurred */
 static void
 trap_dispatch(struct trapframe *tf) {
-    char c;
+    volatile char c;
+    // 有限状态机？
+    static enum {STARTED=0, STOPPED=1, WAITING_FOR_INPUT, READY_TO_OUTPUT} state = STOPPED;
+    // 唉不能long long，看来很有可能会溢出啊
+    static long milliseconds = 0;
+    static enum {COUNTDOWN=-1, COUNTUP=1} mode = COUNTUP;
 
     switch (tf->tf_trapno) {
     case IRQ_OFFSET + IRQ_TIMER:
@@ -159,10 +164,27 @@ trap_dispatch(struct trapframe *tf) {
          * (2) Every TICK_NUM cycle, you can print some info using a funciton, such as print_ticks().
          * (3) Too Simple? Yes, I think so!
          */
-        ticks ++;
-        if (ticks % TICK_NUM == 0) {
-            print_ticks();
+        switch (state) {
+        case STARTED:
+            milliseconds += mode;
+            // 当时间倒计时到0时转成停止状态
+            // 而正计时加了mode之后至少为1所以不会转换状态
+            // 使用小于等于0而不是等于0是为了防止万一出现异常导致小于0的情况
+            state = READY_TO_OUTPUT * (milliseconds <= 0); // 为了减少分支才写成这样
+            break;
+        case READY_TO_OUTPUT:
+            state = STOPPED;
+            mode = COUNTUP;
+            if (milliseconds < 0) milliseconds = 0; // 防止出现异常小于0
+            cprintf(MSG_COUNTDOWN_STOP);
+            break;
+        default:
+            break;
         }
+        ticks ++;
+        // if (ticks % TICK_NUM == 0) {
+        //     print_ticks();
+        // }
         break;
     case IRQ_OFFSET + IRQ_COM1:
         c = cons_getc();
@@ -170,7 +192,58 @@ trap_dispatch(struct trapframe *tf) {
         break;
     case IRQ_OFFSET + IRQ_KBD:
         c = cons_getc();
-        cprintf("kbd [%03d] %c\n", c, c);
+        if (state == WAITING_FOR_INPUT) {
+            long seconds = milliseconds / 1000;
+            // if (c != '\0') cprintf("%c", c);
+             // 如果是正在输入状态，此时不能键入字母或其他各种字符
+            //  在这里不能直接break不然就直接跳出中断处理程序了
+            // 所以用c=0来防止执行后面的转换状态
+            if (c == '\b' || c == '\n' || ('0' <= c && c <= '9')) {
+                cprintf("%c", c);
+            } else {
+                c = '\0';
+            }
+            if (c == '\b') {
+                seconds /= 10;
+            }
+            if ('0' <= c && c <= '9') {
+                seconds *= 10;
+                seconds += c - '0';
+            }
+            milliseconds = seconds * 1000;
+            if (c == '\n') {
+                state = STARTED;
+            }
+            c = '\0'; // 如果是正在输入状态，此时不能根据字母转换状态
+        }
+        switch (c) {
+        case 'a':
+            mode = COUNTUP;
+            cprintf(MSG_COUNTUP_START);
+            break;
+        case 'b':
+            mode = COUNTDOWN;
+            cprintf(MSG_COUNTDOWN_START);
+            state = WAITING_FOR_INPUT;
+            break;
+        case 's':
+        case 'c':
+            state = STARTED;
+            cprintf(MSG_START);
+            break;
+        case 'p':
+            state = STOPPED;
+            cprintf(MSG_PAUSE, milliseconds / 1000, milliseconds % 1000);
+            break;
+        case 'e':
+            state = STOPPED;
+            cprintf(MSG_STOP, milliseconds / 1000, milliseconds % 1000);
+            milliseconds = 0;
+            break;
+        default:
+            break;
+        }
+        // cprintf("kbd [%03d] %c\n", c, c);
         break;
     //LAB1 CHALLENGE 1 : YOUR CODE you should modify below codes.
     case T_SWITCH_TOU:

labcodes_answer/lab1_result/kern/trap/trap.h

@@ -47,6 +47,27 @@
 #define T_SWITCH_TOU                120    // user/kernel switch
 #define T_SWITCH_TOK                121    // user/kernel switch
 
+#define ENGLISH
+#ifndef ENGLISH
+
+#define MSG_COUNTDOWN_STOP "倒计时到0了，停止，转到正计时。\n"
+#define MSG_COUNTUP_START "正计时\n"
+#define MSG_COUNTDOWN_START "倒计时，请输入秒数：\n"
+#define MSG_START "开始\n"
+#define MSG_PAUSE "暂停，当前秒数：%d.%d\n"
+#define MSG_STOP "停止，当前秒数：%d.%d\n"
+
+#else
+
+#define MSG_COUNTDOWN_STOP "Coutdown to 0, stopped, to be countup.\n"
+#define MSG_COUNTUP_START "Countup\n"
+#define MSG_COUNTDOWN_START "Countdown, please input seconds:\n"
+#define MSG_START "Started\n"
+#define MSG_PAUSE "Paused, current seconds: %d.%d\n"
+#define MSG_STOP "Stopped, current seconds: %d.%d\n"
+
+#endif
+
 /* registers as pushed by pushal */
 struct pushregs {
     uint32_t reg_edi;