first pass of some test functions

framebuffer.c

@@ -22,17 +22,31 @@ enum typedef Colors{
 */
 #include "framebuffer.h"
 
-// page 24
-static char* Frame_Buffer = (char*)0x000B8000;
+static char* Frame_Buffer = (char*)FRAME_BUFFER_ADDR;
+static char* Frame_Buffer_End = (char*)(FRAME_BUFFER_ADDR + AREA);
 // Writes character to a given cell in the framebuffer
     // Safety handled by caller function 
+	// also proper location is caller's responsibility
 void write_cell(unsigned cell, char c, char fg, char bg) {
     Frame_Buffer[cell] = c;
     Frame_Buffer[cell+1] = (fg & 0x0f << 4) | (bg & 0x0f);
 }
 
-void colors() {
-    for(int i =0;i<0x10;i++) {
-        write_cell(i, 'a', 8, 8);
-    }
-}
+void clear_buffer() {
+	char* fp = Frame_Buffer;
+	while(fp!=Frame_Buffer_End) {
+		*fp = 0x00;
+	}
+}
+static void print(char* str) {
+	unsigned idx = 0;
+	char* c = str;
+	while(c != 0x00) {
+		write_cell(idx, *c, Green, White);
+		idx += 2;
+	}
+}
+
+void yote() {
+	print("			JankOS			");
+}

framebuffer.h

@@ -2,6 +2,29 @@
 #define ROWS 25
 #define AREA ( COLUMNS * ROWS )
 
+
+#define FRAME_BUFFER_ADDR 0x000B8000
+#define Black 0x01
+#define Blue 0x02
+#define Green 0x03
+#define Cyan 0x04
+#define Red 0x05
+#define Magenta 0x05
+#define Brown 0x06
+#define LightGrey 0x07
+#define DarkGrey 0x08
+#define LightBlue 0x09
+#define LightGreen 0x0a
+#define LightCyan 0x0b
+#define LightRed 0x0c
+#define LightMagenta 0x0d
+#define LightBrown 0x0e
+#define White 0x0f
+
 void write_cell(unsigned cell, char c , char fg, char bg);
 
-void hello();
+void clear_buffer();
+
+static void print(char* str);
+
+void yote();