real mode memory addressing

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tom9876543
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Re: real mode memory addressing

Post by tom9876543 »

GhostXoPCorp wrote:ok i know this may be a dumb question but i just want to make sure

8000:1234 = 81234h? just like 8123:0004 would equal the same?

for all i understand say the bootloader is 0000:7c00
could i do this

1000: 0000-ffff = 64 kb 10000h to 1ffffh
then 2000: 0000- ffff another 64 kb 20000h- 2ffffh
am i able to acsess this with no problems, i know at for example i have to watch out for example 0xb800 but do i have to watch out for that in every segment? do i have to watch out for

0000:b800
1000:b800
2000:b800

im sorry if this is all confusing to ask, but im trying to kill two birds with one stone
Question 1:
Yes 8000:1234 is the same as 8123:004 .

Question 2:
Do a search in Google for the reserved regions of memory in the first 1 megabyte. The answer should be on this web site somewhere.

Question 3:
You have misunderstood b800. That is the SEGMENT, not the offset. b800:XXXX are the addresses you should avoid.
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VolTeK
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Re: real mode memory addressing

Post by VolTeK »

i got that..

Love4Boobies: could u be anymore mouthy?


1. ok?

2. checked google, why do u think i am barely here anymore, i get my information, barely, if at all, from here anymore.

3. i was told that earlier
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Love4Boobies
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Re: real mode memory addressing

Post by Love4Boobies »

GhostXoPCorp wrote:Love4Boobies: could u be anymore mouthy?
:?:

You asked, you've been answered, you asked again, I tried explaining another way. Where did I go wrong?
"Computers in the future may weigh no more than 1.5 tons.", Popular Mechanics (1949)
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AJ
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Re: real mode memory addressing

Post by AJ »

Locked - this thread is going nowhere and some background reading (along with reading replies to the thread) is required.
Locked