[lkml]   [2003]   [Jan]   [13]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
Subjectbootsect.S: 2 questions

I was looking through the linux (2.5.56) arch/i386/boot/bootsect.S and was
puzzled about a couple of things:

1. Near line 221 we have:
sread: .word 0 # sectors read of current track
head: .word 0 # current head
track: .word 0 # current track

However, since a diskette can have at most 2 heads, 80 tracks and 36 sectors
per track, why are these not bytes instead of words especially since space is
at such a tight premium in this code ?

2. Near line 272 we have "movw $7, %bx" but the documentation I've
been able to find about the "int 0x10" BIOS call says that for service
code 0xe (write character and advance cursor), it does not take an
attribute byte input parameter but rather uses the existing attribute. Is
this movw instruction superfluous ?


Do you Yahoo!?
Yahoo! Mail Plus - Powerful. Affordable. Sign up now.
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to
More majordomo info at
Please read the FAQ at

 \ /
  Last update: 2005-03-22 13:32    [W:0.047 / U:0.812 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site