boot directory cleanup continued

1 files changed, 28 insertions, 0 deletions

diff --git a/boot/print_string_16.asm b/boot/print_string_16.asm
new file mode 100644
index 0000000..5d8ad5c
--- /dev/null
+++ b/boot/print_string_16.asm
@@ -0,0 +1,28 @@
+[bits 16]
+
+;print_string routine ([bx])
+;this routine will print a null terminated string at [bx] to the screen.
+print_string:
+
+    pusha			;push all registers
+    mov ah,0x0e
+
+    print_string_loop:
+
+	;check if value at [bx] is "\0" (end of string)
+	mov cl,[bx]
+	cmp cl,0
+	je print_string_finish
+
+	;otherwise instruct BIOS to print the current char
+	mov al,cl
+	int 0x10
+
+	;proceed with next char
+        inc bx
+	jmp print_string_loop
+
+    print_string_finish:
+
+    popa			;pop all registers
+    ret				;return to caller