vbatts/grub
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2002-11-28 Yoshinori K. Okuji <okuji@enbug.org>

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* stage2/asm.S (console_cls): Write spaces to the entire screen
	instead of getting/setting the video mode, because this flickers
	the screen and is quite annoying, if using a LCD.
This commit is contained in:
okuji 2002-11-28 07:40:37 +00:00
parent 6ebab1bf0b
commit a44e6361bc
2 changed files with 26 additions and 10 deletions
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6
ChangeLog
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@ -1,3 +1,9 @@
2002-11-28 Yoshinori K. Okuji <okuji@enbug.org>
* stage2/asm.S (console_cls): Write spaces to the entire screen
instead of getting/setting the video mode, because this flickers
the screen and is quite annoying, if using a LCD.
2002-11-15 Yoshinori K. Okuji <okuji@enbug.org>
* docs/grub.texi (QNX): New subsection. Reported by

30
stage2/asm.S
View file

@ -2128,13 +2128,12 @@ ENTRY(console_gotoxy)
/*
* void console_cls (void)
* BIOS call "INT 10H Function 0Fh" to get current video mode
* Call with %ah = 0x0f
* Returns %al = (video mode)
* BIOS call "INT 10H Function 09h" to write character and attribute
* Call with %ah = 0x09
* %al = (character)
* %bh = (page number)
* BIOS call "INT 10H Function 00h" to set the video mode (clears screen)
* Call with %ah = 0x00
* %al = (video mode)
* %bl = (attribute)
* %cx = (number of times)
*/
@ -2145,10 +2144,21 @@ ENTRY(console_cls)
call EXT_C(prot_to_real)
.code16
movb $0xf, %ah
int $0x10 /* Get Current Video mode */
xorb %ah, %ah
int $0x10 /* Set Video mode (clears screen) */
/* move the cursor to the beginning */
movb $0x02, %ah
xorb %bh, %bh
xorw %dx, %dx
int $0x10
/* write spaces to the entire screen */
movw $0x0920, %ax
movw $0x07, %bx
movw $(80 * 25), %cx
int $0x10
/* move back the cursor */
movb $0x02, %ah
int $0x10
DATA32 call EXT_C(real_to_prot)
.code32