commit b6729e0b95ada1c7074add2ca93ce6c01dca8a9c
from: Benjamin Stürz <benni@stuerz.xyz>
date: Sat Oct 05 22:05:42 2024 UTC

sys: fix putchar()'s scroll back

commit - b8971940d603d9f699f4df57e377391e0c1cd52c
commit + b6729e0b95ada1c7074add2ca93ce6c01dca8a9c
blob - b42ac4bb378bf4a72d4038bddbcb3eea1b851edb
blob + 0c67881007e3e0152772558c01203f1f4e03aebd
--- sys/kernel.asm
+++ sys/kernel.asm
@@ -221,13 +221,20 @@ writech:
 	ret
 
 .scroll:
+	push ds
+	mov ax, 0x18
+	mov ds, ax
+
 	cld
 	xor di, di
-	mov si, 0x160
-	mov cx, 80 * 24 * 2
+	mov si, 160
+	mov cx, 80 * 24
 	rep movsw
 
-	mov si, 80 * 24 * 2
+	pop ds
+
+	mov di, 80 * 24 * 2
+	mov cx, 80
 	mov ax, (' ' | (0x07 << 8))
 	rep stosw
 	mov byte [posy], 24