Compact flash capacity

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Hi,

I'm sure this is easily explained, but I'm curious as to how to
interpret the reported capacities from CF cards. For example, I have a
512MB Hitachi device, which my embedded system tells me has
512,483,328 bytes available, (1000944 addressable sectors in LBA mode)

Plugging the same card into WinHex shows the same number of bytes, but
reports the cards capacity as 489MB- how is this figure arrived at?

I'm wondering if the 'Addressable bytes in LBA mode' figure the CF
controller reports in the CIS data might include 'bad' sectors- Can I
assume from what is reported that it's all useable?

Many thanks

David

Re: Compact flash capacity
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512,483,328 / (1024 * 1024) = 488.7 MB

Rob



Re: Compact flash capacity
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In other words, marketing MB = 1,000,000 bytes, real MB = 1024 * 1024 bytes.

Mike




Re: Compact flash capacity
On Fri, 13 Aug 2004 23:14:02 -0400, Michael Dombrowski

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[...]
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Actually 1 MB = 1,000,000 bytes, 1 MiB = 1,048,576 bytes.  See
http://physics.nist.gov/cuu/Units/binary.html

Regards,

                               -=Dave
--
Change is inevitable, progress is not.

Re: Compact flash capacity
On Mon, 16 Aug 2004 20:22:21 GMT, snipped-for-privacy@hotmail.com (Dave Hansen)

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So 1KB = 1000 bytes?

Mike Harding


Re: Compact flash capacity
On Tue, 17 Aug 2004 07:16:43 -0700, Mike Harding

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kilo = k (lower case)

so 1kB = 1000 bytes
 1 kiB = 1024 bytes

Regards
  Anton


Re: Compact flash capacity
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bytes.

1 kB = 1024 byte, but is not ISO standard compatible
and should probably only be used for semiconductor memory
and not harddisks etc for the future.
1 Pint of beer is also not following ISO standard which is based on the
liter,
but the measure still exist.

Noone is using kiB...

Also, is there anyone caring if a hard disk contains
250 * 1024 * 1024 * 1024 bytes or
250 * 1000 * 1000 * 1000 bytes?

--
Best Regards
Ulf Samuelsson
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Re: Compact flash capacity

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The difference is over 7% so yes plenty of people should care. The disk
manufacturers sales departments care which is why they universally use the
more flattering definition of GB.


Re: Compact flash capacity
On Tue, 17 Aug 2004 00:13:56 +0200, "Ulf Samuelsson"

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Back in the late 1980's I worked for a company that counted IBM
semiconductor fabs as a customer.  A colleague went to one of their
sites (East Fishkill or Essex Junction, IIRC), and saw a sign posted
in a cleanroom (visible from the non-cleanroom touring area) that said

   "1,000,000 bit DRAM"

I never learned for sure if the sign was correct just some marketroids
incorrect transcription of "one megabit."

The big problem with the IEC binary prefixes is that nobody actually
uses them (myself included), except in Usenet posts such as these.

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Heck an American pint isn't even the same thing as an English
(Imperial) pint...

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I feel cheated.  My new development system is supposed to have a 40 GB
hard drive.  And it does.  Problem is, that's only 37.25 GiB...

Regards,

                               -=Dave
--
Change is inevitable, progress is not.

Re: Compact flash capacity
On Mon, 16 Aug 2004 23:47:08 GMT, snipped-for-privacy@hotmail.com (Dave Hansen)

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1,000,000 bit core would be more believable, i.e. 250,000 decimal
digits.

I once wrote a cross-assembler for a non-IBM computer with 1000 words
of memory (addresses 0...999) and IIRC each word contained 12 (BCD)
digits, thus the total memory capacity was 48,000 bits. That would be
48 kbits.

Paul
  

Re: Compact flash capacity
On 17 Aug 2004 07:32:48 GMT, Hans-Bernhard Broeker

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Not me.

1KB (or kb, it doesn't matter) is 2^10.

These are binary electronic terms - trying to make them
decimal is plain silly.

I don't want to try and design 9.87365291 address lines
to service a 1000 byte memory.

Mike Harding


Re: Compact flash capacity
On 13 Aug 2004 06:17:08 -0700, snipped-for-privacy@phylida.co.uk (David Fussell)

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489 MiB = 512,753,664 bytes = 513 Mbytes.


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