X-Git-Url: http://git.mutantstargoat.com/user/nuclear/?a=blobdiff_plain;f=bootcard.asm;h=dddf846518ef6891bd5d87725c3bd6e5325975cd;hb=HEAD;hp=29f0e5c0ed94dca56c817534fc64f7303c80a6d8;hpb=556d5949c6abded2cd793f7adda37adfe9ec5682;p=bootcard

diff --git a/bootcard.asm b/bootcard.asm
index 29f0e5c..dddf846 100644
--- a/bootcard.asm
+++ b/bootcard.asm
@@ -1,15 +1,37 @@
-; boot me!
-; nasm -f bin -o foo.img foo.asm
-; cat foo.img >/dev/<usbstick>
+; ---- boot me! ----
+; nasm -f bin -o bootcard.img bootcard.asm
+; cat bootcard.img >/dev/<usbstick>
 
 	org 7c00h
 	bits 16
 
+barh	equ 4
+nbars	equ 11
+barstart equ 200 - (nbars+1) * barh
+
 nticks	equ 7e00h
 tmoffs	equ 7e04h
 musptr	equ 7e08h
+frame	equ 7e0ch
+fval	equ 7e10h
 cmap	equ 7e14h
 
+%macro setcur 2
+	mov dx, %1 | (%2 << 8)
+	xor bx, bx
+	mov ah, 2
+	int 10h
+%endmacro
+%macro spkon 0
+	in al, 61h
+	or al, 3
+	out 61h, al
+%endmacro
+%macro spkoff 0
+	in al, 61h
+	and al, 0fch
+	out 61h, al
+%endmacro
 %macro stimer 2
 	mov al, (%1 << 6) | 36h
 	out 43h, al
@@ -32,6 +54,7 @@ start:	xor ax, ax
 	cli
 	mov word [32], tintr
 	mov [34], ax
+
 	stimer 0, 5966
 
 	mov ax, 13h
@@ -39,30 +62,21 @@ start:	xor ax, ax
 	push 0a000h
 	pop es
 
+	
 	mov al, 16
-	mov di, 48640
-	mov bx, 11
-.bars:
-	mov cx, 1280
+	mov di, barstart * 320
+	mov bx, nbars
+.drawbars:
+	mov cx, barh * 320
 	rep stosb
 	inc al
 	dec bx
-	jnz .bars
+	jnz .drawbars
 
-	mov dx, 100ch
-	xor bx, bx
-	mov ah, 2
-	int 10h
+	setcur 12, 16
 	mov si, str1
-.txout:	mov al, [si]
-	and al, al
-	jz .done
-	mov ah, 0eh
-	mov bx, 82
-	int 10h
-	inc si
-	jmp .txout
-.done:
+	call textout
+
 	sti
 
 mainloop:
@@ -80,12 +94,13 @@ drawbg:
 .fillgrad:
 	mov ax, bx
 	mov ah, al
-	mov cx, 2400
+	mov cx, 2400 ; 15 lines
 	rep stosw
 	inc bx
 	cmp bx, 208
 	jnz .fillgrad
 
+	; mountains
 	mov cx, 320
 	mov bp, sp
 .mnt:	mov [bp - 2], cx
@@ -109,6 +124,7 @@ drawbg:
 	dec cx
 	jnz .mnt
 
+	; upd colormap
 	mov dx, 3c8h
 	mov al, 16
 	out dx, al
@@ -119,6 +135,18 @@ drawbg:
 
 	jmp mainloop
 
+textout:
+	mov al, [si]
+	and al, al
+	jz .done
+	mov ah, 0eh
+	mov bx, 82
+	int 10h
+	inc si
+	jmp textout
+.done:	ret
+
+
 tintr:
 	pusha
 	mov ax, [nticks]
@@ -153,14 +181,10 @@ tintr:
 
 	mov bx, ax
 	stimer 2, bx
-	in al, 61h
-	or al, 3
-	out 61h, al
+	spkon
 	jmp .end
 
-.off:	in al, 61h
-	and al, 0fch
-	out 61h, al
+.off:	spkoff
 
 .end:	test word [nticks], 1
 	jnz .eoi
@@ -199,3 +223,4 @@ w30:	dw 30
 
 	times 510-($-$$) db 0
 	dw 0aa55h
+; vi:ft=nasm ts=8 sts=8 sw=8: