* address limitation @ 2004-10-08 12:28 Ankit Jain 2004-10-08 22:08 ` Jim Nelson 0 siblings, 1 reply; 4+ messages in thread From: Ankit Jain @ 2004-10-08 12:28 UTC (permalink / raw) To: newbie hi well i am not able ot understand this... there are lot many more problems /proc/iomem 00000000-0009fbff : System RAM 0009fc00-0009ffff : reserved 000a0000-000bffff : Video RAM area 000c0000-000c7fff : Video ROM 000f0000-000fffff : System ROM 00100000-077effff : System RAM 00100000-00250d5b : Kernel code 00250d5c-0034ac43 : Kernel data this is just a brief..... System RAM what does that mean? the range can just point 65K of RAM? what about rest? so what that means? also, on a 32 bit proceesor we can at the most have a access to 4GB of area as we have that many address space. well some what it look stupid but then also asking some where this blunder i have to clear, that how it access the hard disks which is of much high capacity? thanks again ankit ________________________________________________________________________ Yahoo! Messenger - Communicate instantly..."Ping" your friends today! Download Messenger Now http://uk.messenger.yahoo.com/download/index.html - To unsubscribe from this list: send the line "unsubscribe linux-newbie" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.linux-learn.org/faqs ^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: address limitation 2004-10-08 12:28 address limitation Ankit Jain @ 2004-10-08 22:08 ` Jim Nelson 2004-10-09 9:12 ` Ankit Jain 0 siblings, 1 reply; 4+ messages in thread From: Jim Nelson @ 2004-10-08 22:08 UTC (permalink / raw) To: Ankit Jain; +Cc: newbie Ankit Jain wrote: >hi > >well i am not able ot understand this... there are lot >many more problems > >/proc/iomem >00000000-0009fbff : System RAM >0009fc00-0009ffff : reserved >000a0000-000bffff : Video RAM area >000c0000-000c7fff : Video ROM >000f0000-000fffff : System ROM >00100000-077effff : System RAM >00100000-00250d5b : Kernel code >00250d5c-0034ac43 : Kernel data > >this is just a brief..... System RAM what does that >mean? the range can just point 65K of RAM? what about >rest? so what that means? > > Okay, 00000000-0009fbff : System RAM This is the 640 KB that is part of the legacy support for real-mode PC applications. 0009fc00-0009ffff : reserved 000a0000-000bffff : Video RAM area 000c0000-000c7fff : Video ROM 000f0000-000fffff : System ROM This is the BIOS and VGA address area (up to 1 MB), once again to support real-mode PC stuff (DOS, primarily). The original IBM PC's (I think starting with the XT, maybe the PC) had a 20-bit memory addressing scheme, but only 16-bit registers. If you ever want to hop into the way-back machine to the days of CGA's, hardcards, and 5 1/4" floppies, grab a book on DOS programming - FreeDOS (http://www.freedos.org) is still out there, and it's actually kind of fun to run something that blindingly simple :) 00100000-077effff : System RAM Here is the rest of your system's memory. >also, > >on a 32 bit proceesor we can at the most have a access >to 4GB of area as we have that many address space. >well some what it look stupid but then also asking >some where this blunder i have to clear, that how it >access the hard disks which is of much high capacity? > > Hard disks are controlled by sending requests to and from the drive for blocks of data. Sort of like reading a book - you only see a couple of pages at a time, but you can access the whole book, or any section of it, by flipping to the right page number. Same way with the hard disk controller. Ask it for sector 11432, and it will give it to you (oversimplified, but essentially correct). - To unsubscribe from this list: send the line "unsubscribe linux-newbie" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.linux-learn.org/faqs ^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: address limitation 2004-10-08 22:08 ` Jim Nelson @ 2004-10-09 9:12 ` Ankit Jain 2004-10-09 9:44 ` Jim Nelson 0 siblings, 1 reply; 4+ messages in thread From: Ankit Jain @ 2004-10-09 9:12 UTC (permalink / raw) To: Jim Nelson; +Cc: newbie Thanks a lot for help rest inline:) --- Jim Nelson <james4765@verizon.net> wrote: > Ankit Jain wrote: > > >hi > > > >well i am not able ot understand this... there are > lot > >many more problems > > > >/proc/iomem > >00000000-0009fbff : System RAM > >0009fc00-0009ffff : reserved > >000a0000-000bffff : Video RAM area > >000c0000-000c7fff : Video ROM > >000f0000-000fffff : System ROM > >00100000-077effff : System RAM > >00100000-00250d5b : Kernel code > >00250d5c-0034ac43 : Kernel data > > > >this is just a brief..... System RAM what does that > >mean? the range can just point 65K of RAM? what > about > >rest? so what that means? > > > > > > Okay, > > 00000000-0009fbff : System RAM > > This is the 640 KB that is part of the legacy > support for real-mode PC > applications. > > 0009fc00-0009ffff : reserved > 000a0000-000bffff : Video RAM area > 000c0000-000c7fff : Video ROM > 000f0000-000fffff : System ROM > > > This is the BIOS and VGA address area (up to 1 MB), > once again to > support real-mode PC stuff (DOS, primarily). The > original IBM PC's (I > think starting with the XT, maybe the PC) had a > 20-bit memory addressing > scheme, but only 16-bit registers. If you ever want > to hop into the > way-back machine to the days of CGA's, hardcards, > and 5 1/4" floppies, > grab a book on DOS programming - FreeDOS > (http://www.freedos.org) is > still out there, and it's actually kind of fun to > run something that > blindingly simple :) > > 00100000-077effff : System RAM > > > Here is the rest of your system's memory. > > > >also, > > > >on a 32 bit proceesor we can at the most have a > access > >to 4GB of area as we have that many address space. > >well some what it look stupid but then also asking > >some where this blunder i have to clear, that how > it > >access the hard disks which is of much high > capacity? > > > > > Hard disks are controlled by sending requests to and > from the drive for > blocks of data. Sort of like reading a book - you > only see a couple of > pages at a time, but you can access the whole book, > or any section of > it, by flipping to the right page number. Same way > with the hard disk > controller. Ask it for sector 11432, and it will > give it to you > (oversimplified, but essentially correct). thanks again but according to this concepts of pages if the size is of size 40 GB then size of each page should be 10kb is it correct...becaz when only it will be able to map the complete hard disk.... thanks again > > - > To unsubscribe from this list: send the line > "unsubscribe linux-newbie" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at > http://vger.kernel.org/majordomo-info.html > Please read the FAQ at > http://www.linux-learn.org/faqs > ________________________________________________________________________ Yahoo! Messenger - Communicate instantly..."Ping" your friends today! Download Messenger Now http://uk.messenger.yahoo.com/download/index.html - To unsubscribe from this list: send the line "unsubscribe linux-newbie" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.linux-learn.org/faqs ^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: address limitation 2004-10-09 9:12 ` Ankit Jain @ 2004-10-09 9:44 ` Jim Nelson 0 siblings, 0 replies; 4+ messages in thread From: Jim Nelson @ 2004-10-09 9:44 UTC (permalink / raw) To: Ankit Jain; +Cc: newbie Ankit Jain wrote: >Thanks a lot for help > >rest inline:) > --- Jim Nelson <james4765@verizon.net> wrote: > > >>Ankit Jain wrote: >> >> >> >>>hi >>> >>>well i am not able ot understand this... there are >>> >>> >>lot >> >> >>>many more problems >>> >>>/proc/iomem >>>00000000-0009fbff : System RAM >>>0009fc00-0009ffff : reserved >>>000a0000-000bffff : Video RAM area >>>000c0000-000c7fff : Video ROM >>>000f0000-000fffff : System ROM >>>00100000-077effff : System RAM >>>00100000-00250d5b : Kernel code >>>00250d5c-0034ac43 : Kernel data >>> >>>this is just a brief..... System RAM what does that >>>mean? the range can just point 65K of RAM? what >>> >>> >>about >> >> >>>rest? so what that means? >>> >>> >>> >>> >>Okay, >> >>00000000-0009fbff : System RAM >> >>This is the 640 KB that is part of the legacy >>support for real-mode PC >>applications. >> >>0009fc00-0009ffff : reserved >>000a0000-000bffff : Video RAM area >>000c0000-000c7fff : Video ROM >>000f0000-000fffff : System ROM >> >> >>This is the BIOS and VGA address area (up to 1 MB), >>once again to >>support real-mode PC stuff (DOS, primarily). The >>original IBM PC's (I >>think starting with the XT, maybe the PC) had a >>20-bit memory addressing >>scheme, but only 16-bit registers. If you ever want >>to hop into the >>way-back machine to the days of CGA's, hardcards, >>and 5 1/4" floppies, >>grab a book on DOS programming - FreeDOS >>(http://www.freedos.org) is >>still out there, and it's actually kind of fun to >>run something that >>blindingly simple :) >> >>00100000-077effff : System RAM >> >> >>Here is the rest of your system's memory. >> >> >> >> >>>also, >>> >>>on a 32 bit proceesor we can at the most have a >>> >>> >>access >> >> >>>to 4GB of area as we have that many address space. >>>well some what it look stupid but then also asking >>>some where this blunder i have to clear, that how >>> >>> >>it >> >> >>>access the hard disks which is of much high >>> >>> >>capacity? >> >> >>> >>> >>> >>> >>Hard disks are controlled by sending requests to and >>from the drive for >>blocks of data. Sort of like reading a book - you >>only see a couple of >>pages at a time, but you can access the whole book, >>or any section of >>it, by flipping to the right page number. Same way >>with the hard disk >>controller. Ask it for sector 11432, and it will >>give it to you >>(oversimplified, but essentially correct). >> >> > >thanks again but according to this concepts of pages >if the size is of size 40 GB then size of each page >should be 10kb > >is it correct...becaz when only it will be able to map >the complete hard disk.... > >thanks again > > > > Actually, it's 512 bytes - one sector. As far as I can tell (looking at a book I've got) at the most, the IDE controllers can handle a read/write request of 256 sectors * 512 bytes = 128 KB. The actual mapping of the hard drive is done at a number of levels. You have the actual hardware addressing scheme (most modern hard drives use a system not too dissimilar to SCSI drives), on which you put a partition table (to divide the raw disk into chunks), and in each you put a filesystem (that keeps track of which chunk of which file is put where). Different filesystems work in different ways - the FAT filesystem on floppies, USB camera memory cards, and DOS/Windows partitions, the ext2/ext3 filesystem that is the standard Red Hat filesystem, Reiserfs which is standard with SuSE and newer Slackware, and many, many others that are used for interoperability with other UNIX variants, or work on embedded systems, or work on DVD-ROM, etc. - To unsubscribe from this list: send the line "unsubscribe linux-newbie" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.linux-learn.org/faqs ^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2004-10-09 9:44 UTC | newest] Thread overview: 4+ messages (download: mbox.gz follow: Atom feed -- links below jump to the message on this page -- 2004-10-08 12:28 address limitation Ankit Jain 2004-10-08 22:08 ` Jim Nelson 2004-10-09 9:12 ` Ankit Jain 2004-10-09 9:44 ` Jim Nelson
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