From: John Tsiombikas <nuclear@member.fsf.org>
Date: Tue, 5 Jul 2022 05:04:29 +0000 (+0300)
Subject: it works! (on some machines, let's investigate further)
X-Git-Url: http://git.mutantstargoat.com/user/nuclear/?p=efitest3;a=commitdiff_plain;h=2dd595122e5ef1aca0e050acea929560c54dc7aa

it works! (on some machines, let's investigate further)
---

diff --git a/Makefile b/Makefile
index 5f0c29f..11d2bd2 100644
--- a/Makefile
+++ b/Makefile
@@ -1,3 +1,6 @@
+.PHONY: all
+all: disk.img
+
 bootx64.efi: efitest.bin hdr.asm
 	nasm -o $@ -f bin hdr.asm
 
diff --git a/efitest.asm b/efitest.asm
index 333b095..0feb61d 100644
--- a/efitest.asm
+++ b/efitest.asm
@@ -142,13 +142,39 @@ start16:
 	mov ax, 13h
 	int 10h
 
+	; setup palette
+	mov dx, 3c8h
+	xor al, al
+	out dx, al
+	inc dx
+	xor cl, cl
+.pal:	mov al, cl
+	out dx, al
+	xor al, al
+	out dx, al
+	mov al, cl
+	not al
+	out dx, al
+	inc cl
+	jnz .pal
+
+	; fill framebuffer with xor pattern
 	mov ax, 0a000h
 	mov es, ax
 	xor di, di
-	mov cx, 32000
-	mov ax, 6767h
-	rep stosw
-
+	xor cx, cx
+.yloop:	xor dx, dx
+.xloop:	mov ax, dx
+	xor ax, cx
+	stosb
+	inc dx
+	cmp dx, 320
+	jnz .xloop
+	inc cx
+	cmp cx, 200
+	jnz .yloop
+
+	; halt for ever
 .hang:	hlt
 	jmp .hang