Royalties for use of an SDCard

29 posts / 0 new
Last post
  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

Quote:

What's your sense for UDF's effect on an SD card's lifetime?

As the wear levelling is performed at a lower level than either FAT or UDF then it should be the same. I don't think UDF has any greater propensity to repeatedly write sectors than FAT does. In fact depending how FAT is used (and whether the implementation implements it) things like the FsInfo sector can get a real hammering (I know this from the days of working on PVR hard drives!). But like an HDD an SD should have a re-map sector pool and if a sector cannot be written it should be invisibly remapped to one of the spare sectors and if that then goes bad it too would be remapped and so on.

 

  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

gchapman wrote:
cmatias wrote:
Does anybody know whether I have to pay any kind of royalty to the SD Card association?
Likely no if one uses the Simplified Specifications though there is the statement "... may require a license ...".
References:
One Laptop Per Child, [Community-news] OLPC News (2006-09-16), event 4.
https://en.wikipedia.org/wiki/SD_card#Openness_of_the_standard; note Linux.
The simplified spec has 4-bit SD mode, 1-bit SD mode, SPI mode.
What's missing from the full spec: ultra-high speed, signal voltage level switch, internal write protection, content protection, general command, some switch function commands, memory array, some spec for speed class, some SDXC spec, hot plug (card detect, power protection), programmable card drive, 3.3V signaling, 1.8V drive and signaling, ESD, SPI timing diagrams, some bits from ASSD (Advanced Security SD).

The simplified specification is just a document describing the system. It does not convey any permission to actually *make use* of the information in any particular product. Indeed, the opening of Simplified Host specification document specifically states:

Quote:
No license is granted by implication, estoppel or otherwise under any patent or other rights of the SD Card Association or any third party.

Similarly, the ITU makes the specification documents for h.264 video encoding available as a free download. However, in countries where software patents are held to be valid, you would still have to pay royalties to distribute any software that actually implemented the specification.

FAT16 (without LFN) has been out in the wild long enough now (since the mid 1980s), that it would be next to impossible for any valid patent to still be in effect which could impact its operation. I honestly don't know if FAT32 was ever patented as a separate entity from FAT16.

Of course, patents specifically related to LFN would apply equally to both FAT16 and FAT32 implementations. (As well as FAT12, for that matter, because LFN is supported on floppy discs too.) The good news, though, is that LFN patents were filed and granted around 1995-1996, so in jurisdictions with 20-year-from-filing patent terms, they have no more than 4 years of life left.

  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

I thought the theory was that you could use SD cards in MMC mode (if they are less than 2G, and if they support it) without licensing. Is SPI mode the same as MMC mode? (and if not, does the various code that's around use SD/SPI mode or MMC mode?)

  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

Quote:

Is SPI mode the same as MMC mode?

Yes, so all this is saying $3,000/year please though there is a suggestion you don't have to be a member to get a licence - in which case $1,000/year.

 

  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0
  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

That link is dead

 

  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

westfw wrote:
I thought the theory was that you could use SD cards in MMC mode (if they are less than 2G, and if they support it) without licensing. Is SPI mode the same as MMC mode? (and if not, does the various code that's around use SD/SPI mode or MMC mode?)

There is one point early in the initialization stage where, if you follow the standard SPI initialization procedure as outlined in the MMC specifications, an SD card may fail to initialize.

MMC uses CMD1 to identify card capability and capacity. In SD cards, ACMD41 is recommended to be used instead.

In the current revision of the SD card simplified spec, CMD1 has been removed; modern SD cards are not obliged to support it. SDHC cards, in particular, cannot provide complete capacity information using only the data contained in a CMD1 response. So:
1) You may not succeed initializing a standard SD card relying on CMD1.
2) You are guaranteed to fail to initialize an SDHC card relying on CMD1.

There is no such thing as ACMD41 in the MMC spec. Therefore, any developer that makes use of ACMD41 cannot possibly have obtained knowledge about the existence of ACMD41 through MMC licensing; they must have obtained knowledge of ACMD41's existence through reliance on proprietary intellectual property related specifically to SD cards.

  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

Pay to play, or, switch to MMC at about 10USD/GB; then spend the money on a USB VID or a MAC address.

  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

http://arstechnica.com/microsoft/news/2010/10/microsoft-sues-motorola-citing-android-patent-infringement.ars
(from FAT on wikipedia) lists the patents in the complaint. For this thread's topic looks like just LFN.
FatFs: An Open Source File System by Erich Styger
states (on page 11) that FAT12 and FAT16 are standards without LFN; FAT32 and/or LFN may need licenses.

  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

Quote:

(from FAT on wikipedia) lists the patents in the complaint. For this thread's topic looks like just LFN.

Yes but read the Microsoft site - they seem to be suggesting that they may retroactively chase for more than just LFN

 

Pages