From fedca16fb57e1094e044d24cbaf344d180dbc5b9 Mon Sep 17 00:00:00 2001
From: 423A35C7 <609514299@qq.com>
Date: Wed, 27 Mar 2024 10:35:34 +0800
Subject: [PATCH] =?UTF-8?q?=E6=94=B9=E5=96=84=E4=BA=86=E8=B5=B0=E6=97=B6?=
 =?UTF-8?q?=E4=B8=8D=E5=87=86=E7=9A=84=E9=97=AE=E9=A2=98=EF=BC=8C=E5=80=92?=
 =?UTF-8?q?=E8=AE=A1=E6=97=B6=E6=89=8B=E5=8A=A8=E5=81=9C=E6=AD=A2=E5=90=8E?=
 =?UTF-8?q?=E8=BD=AC=E4=B8=BA=E6=AD=A3=E8=AE=A1=E6=97=B6=EF=BC=8C=E5=A2=9E?=
 =?UTF-8?q?=E5=8A=A0=E4=BA=86=E4=B8=AD=E8=8B=B1=E6=96=87=E5=88=87=E6=8D=A2?=
 =?UTF-8?q?=E7=9A=84=E8=AF=B4=E6=98=8E=E3=80=82?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 labcodes_answer/lab1_result/kern/driver/clock.c | 5 +++--
 labcodes_answer/lab1_result/kern/trap/trap.c    | 6 ++++--
 labcodes_answer/lab1_result/kern/trap/trap.h    | 3 ++-
 3 files changed, 9 insertions(+), 5 deletions(-)

diff --git a/labcodes_answer/lab1_result/kern/driver/clock.c b/labcodes_answer/lab1_result/kern/driver/clock.c
index 41c862e..74a7297 100644
--- a/labcodes_answer/lab1_result/kern/driver/clock.c
+++ b/labcodes_answer/lab1_result/kern/driver/clock.c
@@ -33,8 +33,9 @@ void
 clock_init(void) {
     // set 8253 timer-chip
     outb(TIMER_MODE, TIMER_SEL0 | TIMER_RATEGEN | TIMER_16BIT);
-    outb(IO_TIMER1, TIMER_DIV(1000) % 256);
-    outb(IO_TIMER1, TIMER_DIV(1000) / 256);
+    // 经过多次试验发现原始的10毫秒一次中断（即除以100）是最准时的，不要擅自改中断频率
+    outb(IO_TIMER1, TIMER_DIV(100) % 256);
+    outb(IO_TIMER1, TIMER_DIV(100) / 256);
 
     // initialize time counter 'ticks' to zero
     ticks = 0;
diff --git a/labcodes_answer/lab1_result/kern/trap/trap.c b/labcodes_answer/lab1_result/kern/trap/trap.c
index c209f08..89cb96f 100644
--- a/labcodes_answer/lab1_result/kern/trap/trap.c
+++ b/labcodes_answer/lab1_result/kern/trap/trap.c
@@ -9,7 +9,7 @@
 #include <console.h>
 #include <kdebug.h>
 #include <string.h>
-#define TICK_NUM 100
+#define TICK_NUM 1
 
 static void print_ticks() {
     cprintf("%d ticks\n",TICK_NUM);
@@ -167,7 +167,8 @@ trap_dispatch(struct trapframe *tf) {
         switch (state) {
         case STARTED:
             if (ticks % TICK_NUM == 0) {
-                milliseconds += mode * TICK_NUM;
+                // 10毫秒触发一次时钟中断，TICK_NUM次中断触发一次更新，所以毫秒数应该乘TICK_NUM * 10
+                milliseconds += mode * TICK_NUM * 10;
                 // 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
@@ -239,6 +240,7 @@ trap_dispatch(struct trapframe *tf) {
             break;
         case 'e':
             state = STOPPED;
+            mode = COUNTUP;
             cprintf(MSG_STOP, milliseconds / 1000, milliseconds % 1000);
             milliseconds = 0;
             break;
diff --git a/labcodes_answer/lab1_result/kern/trap/trap.h b/labcodes_answer/lab1_result/kern/trap/trap.h
index 305950c..174e96f 100644
--- a/labcodes_answer/lab1_result/kern/trap/trap.h
+++ b/labcodes_answer/lab1_result/kern/trap/trap.h
@@ -47,7 +47,8 @@
 #define T_SWITCH_TOU                120    // user/kernel switch
 #define T_SWITCH_TOK                121    // user/kernel switch
 
-#define ENGLISH
+// 在VSCode中可以正常看到中文，但在QEMU中看到的是乱码
+#define ENGLISH // 使用中文则不需要这一行
 #ifndef ENGLISH
 
 #define MSG_COUNTDOWN_STOP "倒计时到0了，停止，转到正计时。\n"