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Homework Help: Memory Space

  1. Mar 3, 2008 #1
    The largest memory space that can be addressed by 18 addressing bits is....


    Is there a formula for this perhaps?
     
  2. jcsd
  3. Mar 3, 2008 #2

    chroot

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    How many different combinations of 18 ones and zeros are there?

    - Warren
     
  4. Mar 3, 2008 #3
    2^n
    n=18

    2^18= 262,144
     
  5. Mar 4, 2008 #4
    Would that be 262,144 bytes then
     
  6. Mar 4, 2008 #5

    HallsofIvy

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    Assuming that each "memory location" holds one byte, yes.
     
  7. Mar 4, 2008 #6
    Thanks for the help?
     
  8. Mar 4, 2008 #7
    Something to note - while you might be able to have addresses going all the way up to 2^18 alot of chips do not have memory locations for all of the addresses. Such as variants in the PIC16F8X range.
     
  9. Mar 6, 2008 #8
    I noticed in a Digital Circuits book that with 18 address leads it should be 256K. So where does my 262,144 come from with 2^18. Just a thought?
     
  10. Mar 6, 2008 #9

    chroot

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    256 * 1,024 = 262,144. The "k" in this context means 1,024, not 1,000.

    - Warren
     
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