Talk:Binary prefix/Archive 1

message: In the page, I see the quote: Electronic memory such as RAM and ROM always uses the binary versions, because the physical structure of the device makes it naturally come in sizes that are powers of two.
This isn't true, but I don't yet know how to fix it concisely, help.
For example, flash is an electronic memory, and ECC-protected RAM is an electronic memory, but their capacities aren't naturally powers of two.
A concise true alternative I saw said recently was: The RAM and ROM folk gave us this confusion by behaving as if memory were reliable.  That is, by converting to precise binary prefixes from loose decimal approximations, they left no room for ECC, etc.
In more detail ...
All that's naturally a power of two in memory is the count of raw cells in a single layer.
Yes, P * Q cells appear in a rectangular array.  P * Q is a power of 2 because P and Q are powers of 2.  P and Q are powers of 2 because pins cost much money.  If you make N pins into an address bus, then you can address 2^N rows or columns.  Yes.  So far so good.
But electronic memory today - 2005 - often contains a lot more than a single layer of raw 1 or 0 cells.  As in modems, so now in memory cells, the discrete stored voltage may be multilevel, e.g., representing 0 or 1 or 2 or 3 or 4, not always binary.  The chip may contain more than one layer.  Part of the chip may be dedicated to ECC, or left free for wear-leveling.
Consequently, the capacity of flash memory in particular is now "continuously variable", and their physicists follow the HDD physicists by using the standard metric units to count bits.
—Preceding unsigned comment added by 65.241.179.2 (talk • contribs) 15:32, 23 January 2005
: Memory controllers on motherboards always address whole bytes (which includes any parity or ecc bits) or whole words (whole multiples of whole bytes) in chunks measured in binary multiples.  This is because binary math is the natural form for practically all processors.  The presence of ECC in RAM makes no difference.  The ECC bits are part of the byte, even though the ECC bits are not sent to the CPU, the memory controller reads the extra bits when it reads the byte.  RAM modules are always measured according to how many binary multiple bytes are available no matter how wide the data path is.
: "Flash memory" today refers to non-volitile storage devices that are accessed exactly like hard drives.  They use virtual cylinder, head, and sector specifications for the computer system to address the device and even though they contain memory that is accessed in a "random" (non-serial) method, in discreet rows and columns, it is not considered "RAM".
: Yes, Flash often uses multilevel cell technology, but the data is converted to a binary representation.  So even though one cell can hold more than a simple on/off representation, the absolute capacity is still a function of bits and bytes.  And the memory used by the CPU through the memory controller does not yet use multilevel cell technology.  DDR and RAMBUS are still ones and zeros.
: Flash manufacturers have followed the hard disk drive path to designate capacity, decimal.  No matter how many ECC cells or spare cells for wear-leveling are allocated, the capacity is based on decimal multiples and does not include the spares and ECC.
: So I guess I would say, instead of,  "Electronic memory such as RAM and ROM always uses the binary versions, because the physical structure of the device makes it naturally come in sizes that are powers of two. I propose, "RAM memory modules always designate capacity in binary multiples because that type of math is "native" to binary processors. or " because CPU's use RAM in binary multiples and building RAM modules according to that system is most logical."
: JJLatWiki 18 July 2005 09:11 (Pacific Daylight)
:: "Flash memory" today refers to non-volitile storage devices that are accessed exactly like hard drives.
:: Large flash units used for bulk storage are certainly treated like hard drives but bare flash chips and flash used in microcontrolors for program storage is far more like a more conviniant to use variant of EPROM (reads out like rom, requires special actions for programming) Plugwash 23:53, 16 June 2006 (UTC)
thread_title:  Binary or decimal context implied by electronic memory