lesson 20, preliminar

20-interrupts-timer/kernel/kernel.c

@@ -0,0 +1,9 @@
+#include "../cpu/isr.h"
+#include "../cpu/timer.h"
+
+void main() {
+    isr_install();
+
+    asm volatile("sti");
+    init_timer(50);
+}

20-interrupts-timer/kernel/util.c

@@ -0,0 +1,30 @@
+#include "util.h"
+
+void memory_copy(char *source, char *dest, int nbytes) {
+    int i;
+    for (i = 0; i < nbytes; i++) {
+        *(dest + i) = *(source + i);
+    }
+}
+
+void memory_set(u8 *dest, u8 val, u32 len) {
+    u8 *temp = (u8 *)dest;
+    for ( ; len != 0; len--) *temp++ = val;
+}
+
+/**
+ * K&R implementation
+ */
+void int_to_ascii(int n, char str[]) {
+    int i, sign;
+    if ((sign = n) < 0) n = -n;
+    i = 0;
+    do {
+        str[i++] = n % 10 + '0';
+    } while ((n /= 10) > 0);
+
+    if (sign < 0) str[i++] = '-';
+    str[i] = '\0';
+
+    /* TODO: implement "reverse" */
+}

20-interrupts-timer/kernel/util.h

@@ -0,0 +1,10 @@
+#ifndef UTIL_H
+#define UTIL_H
+
+#include "../cpu/types.h"
+
+void memory_copy(char *source, char *dest, int nbytes);
+void memory_set(u8 *dest, u8 val, u32 len);
+void int_to_ascii(int n, char str[]);
+
+#endif