Add 21 day code

21_day/mouse.c

@@ -0,0 +1,76 @@
+/* 鼠标控制代码 */
+
+#include "bootpack.h"
+
+struct FIFO32 *mousefifo;
+int mousedata0;
+
+void inthandler2c(int *esp)
+/* 来自PS/2鼠标的中断 */
+{
+	int data;
+	io_out8(PIC1_OCW2, 0x64); /* 把IRQ-12接收信号结束的信息通知给PIC1 */
+	io_out8(PIC0_OCW2, 0x62); /* 把IRQ-02接收信号结束的信息通知给PIC0 */
+	data = io_in8(PORT_KEYDAT);
+	fifo32_put(mousefifo, data + mousedata0);
+	return;
+}
+
+#define KEYCMD_SENDTO_MOUSE   0xd4
+#define MOUSECMD_ENABLE     0xf4
+
+void enable_mouse(struct FIFO32 *fifo, int data0, struct MOUSE_DEC *mdec)
+{
+	/* 将FIFO缓冲区的信息保存到全局变量里 */
+	mousefifo = fifo;
+	mousedata0 = data0;
+	/* 鼠标有效 */
+	wait_KBC_sendready();
+	io_out8(PORT_KEYCMD, KEYCMD_SENDTO_MOUSE);
+	wait_KBC_sendready();
+	io_out8(PORT_KEYDAT, MOUSECMD_ENABLE);
+	/* 顺利的话，ACK(0xfa)会被发送*/
+	mdec->phase = 0; /* 等待鼠标的0xfa的阶段*/
+return;
+}
+
+int mouse_decode(struct MOUSE_DEC *mdec, unsigned char dat)
+{
+	if (mdec->phase == 0) {
+		/* 等待鼠标的0xfa的阶段 */
+		if (dat == 0xfa) {
+			mdec->phase = 1;
+		}        
+		return 0;
+	}
+	if (mdec->phase == 1) {
+		/* 等待鼠标第一字节的阶段 */
+		mdec->buf[0] = dat;
+		mdec->phase = 2;
+		return 0;
+	}
+	if (mdec->phase == 2) {
+		/* 等待鼠标第二字节的阶段 */
+		mdec->buf[1] = dat;
+		mdec->phase = 3;
+		return 0;
+	}
+	if (mdec->phase == 3) {
+		/* 等待鼠标第二字节的阶段 */
+		mdec->buf[2] = dat;
+		mdec->phase = 1;
+		mdec->btn = mdec->buf[0] & 0x07;
+		mdec->x = mdec->buf[1];
+		mdec->y = mdec->buf[2];
+		if ((mdec->buf[0] & 0x10) != 0) {
+			mdec->x |= 0xffffff00;
+		}
+		if ((mdec->buf[0] & 0x20) != 0) {
+			mdec->y |= 0xffffff00;
+		}      
+		mdec->y = - mdec->y; /* 鼠标的y方向与画面符号相反 */  
+		return 1;
+	}
+	/* 应该不可能到这里来 */
+	return -1; 
+}