- fixed potentially incorrect ds in timer interrupt

- fixed vsync routine redrawing while waiting
- shaved off a couple of bytes

diff --git a/bootcard.asm b/bootcard.asm
index 9f70b59..f823219 100644 (file)
--- a/bootcard.asm
+++ b/bootcard.asm
@@ -25,8 +25,7 @@ KB_CTRL               equ 61h
 %define DIV_ROUND(a, b)        ((a) / (b) + ((a) % (b)) / ((b) / 2))
 
 %macro setcursor 2
-       mov dl, %1
-       mov dh, %2
+       mov dx, %1 | (%2 << 8)
        xor bx, bx
        mov ah, 2
        int 10h
@@ -75,14 +74,6 @@ start:       xor ax, ax
 mainloop:
        call drawbg
 
-       mov dx, 3dah
-.invb: in al, dx
-       and al, 8
-       jnz mainloop
-.novb: in al, dx
-       and al, 8
-       jz .novb
-
        push ds
        push es
        push es
@@ -92,6 +83,15 @@ mainloop:
        xor di, di
        xor si, si
        mov cx, 32000
+
+       mov dx, 3dah
+.invb: in al, dx
+       and al, 8
+       jnz .invb
+.novb: in al, dx
+       and al, 8
+       jz .novb
+
        rep movsw
        pop es
        pop ds
@@ -157,6 +157,9 @@ textout:
 
 timer_intr:
        pusha
+       push ds
+       push word 0
+       pop ds
        mov ax, [nticks]
        inc ax
        mov [nticks], ax
@@ -183,6 +186,7 @@ timer_intr:
 
 .eoi:  mov al, 20h
        out 20h, al     ; EOI
+       pop ds
        popa
        iret