From d63c2cbd69aa87da8bdcd8cef3e3e71d7b251cf5 Mon Sep 17 00:00:00 2001
From: Robbe Van Herck <robbevanherck1@gmail.com>
Date: Fri, 14 Jun 2019 11:01:36 +0200
Subject: [PATCH] Stub serial

---
 messages.asm | 36 +++++++++++++++++++++++++++++++-----
 1 file changed, 31 insertions(+), 5 deletions(-)

diff --git a/messages.asm b/messages.asm
index 9a77527..74e3c3d 100644
--- a/messages.asm
+++ b/messages.asm
@@ -21,6 +21,9 @@ mov dh, HEIGHT
 mov dl, WIDTH
 int 0x10
 
+;; Turn on interrupts
+sti
+
 ;; Set cursor to bottom of screen
 mov dh, HEIGHT
 mov dl, 0x00
@@ -28,10 +31,33 @@ mov bh, 0x00
 mov ah, 0x02
 int 0x10
 
+;; Start serial connection
+mov ah, 0
+mov al, 0b11100011
+mov dx, 0
+int 0x14
+
 .loop:
-        ;; Read character
-        mov ah, 0x00
-        int 0x16
+        ;; Print a '.' to debug
+        mov ah, 0x01
+        mov al, '.'
+        mov dx, 0
+        int 0x14
+
+
+        ;; Check status of COM1
+        mov ah, 0x03
+        mov dx, 0
+        int 0x14
+
+        ;; If not ok, wait
+        and ah, 0x01
+        jz .loop
+
+        ;; If ok, start reading character
+        mov ah, 0x02
+        mov dx, 0
+        int 0x14
 
         cmp al, 0x0d ; newline
         je .newline
@@ -72,11 +98,11 @@ int 0x10
 .nonewline:
 
         ;; Write character
-	    mov ah, 0x09
+        mov ah, 0x09
         mov bh, 0x00
         mov bl, [color_mode]
         mov cx, 0x01
-	    int 0x10
+        int 0x10
 
         ;; Get current cursor position
         mov ah, 0x03