Forums

why not just say I2C?

Started by tim December 20, 2004
I am currently working with a range of peripherals whos
control lines look remarkably like an I2C interface.

The data sheets go into great detail about how the data and
clock line are used to communicate with the device and how
it has an own 'address' so that you can differentiate it from
other devices etc.......

Why not just say that it's an I2C comptable device FFS.

Do they have to pay Philips some extra money for admitting
that it's I2C rather than pretending that it is something else?

(and is it really still in patent after 20 years?)

sorry rant over.

tim




Just call it SPI like everybody else. It's probably more of a trademark
than a patent issue in the same way you can't call your latest vacuum
cleaner a Hoover.
Peter

On 2004-12-20, peterk <peterk.vt80@gmail.com> wrote:

> Just call it SPI like everybody else.
Because I2C and SPI aren't very similar at all? -- Grant Edwards grante Yow! I'LL get it!! It's at probably a FEW of my visi.com ITALIAN GIRL-FRIENDS!!
SPI is not I2C. SPI is to "three-wire interface" as I2C is to "two wire
interface". Or to put it another way, SPI is to Motorola as I2C is to
Philips.

Also, note that "I2C-like" peripherals are in no way guaranteed to be
FULLY I2C compatible.

On 20 Dec 2004 13:22:36 -0800, the renowned "peterk"
<peterk.vt80@gmail.com> wrote:

>Just call it SPI like everybody else. It's probably more of a trademark >than a patent issue in the same way you can't call your latest vacuum >cleaner a Hoover. >Peter
I think you mean "two wire". Best regards, Spehro Pefhany -- "it's the network..." "The Journey is the reward" speff@interlog.com Info for manufacturers: http://www.trexon.com Embedded software/hardware/analog Info for designers: http://www.speff.com
Oops, of course you are right, it's TWI. I should put my brain into
gear before writing.
Peter

In article <cq7eol$ac4$00$1@news.t-online.com>, 
520010973502.removethis@t-online.de says...
> > I am currently working with a range of peripherals whos > control lines look remarkably like an I2C interface. > > The data sheets go into great detail about how the data and > clock line are used to communicate with the device and how > it has an own 'address' so that you can differentiate it from > other devices etc....... > > Why not just say that it's an I2C comptable device FFS. > > Do they have to pay Philips some extra money for admitting > that it's I2C rather than pretending that it is something else? > > (and is it really still in patent after 20 years?) > > sorry rant over. > > tim
Well, yes, they DO have to pay Philips if they use the term "I2C" or "IIC". In exchange, Philips grants them a unique device identifier for their product. It's also a trademark. --Gene
On Tue, 21 Dec 2004 00:32:17 -0500, Gene S. Berkowitz <first.last@comcast.net> wrote:

>In article <cq7eol$ac4$00$1@news.t-online.com>, >520010973502.removethis@t-online.de says... >> >> I am currently working with a range of peripherals whos >> control lines look remarkably like an I2C interface. >> >> The data sheets go into great detail about how the data and >> clock line are used to communicate with the device and how >> it has an own 'address' so that you can differentiate it from >> other devices etc....... >> >> Why not just say that it's an I2C comptable device FFS. >> >> Do they have to pay Philips some extra money for admitting >> that it's I2C rather than pretending that it is something else? >> >> (and is it really still in patent after 20 years?) >> >> sorry rant over. >> >> tim > >Well, yes, they DO have to pay Philips if they use the term "I2C" or >"IIC". >In exchange, Philips grants them a unique device identifier for their >product.
Not always - only if it is a new type of device - e.g. all eeproms have the same address prefix.
Last I heard, I2C was a registered trademark and you had to pay Philips
for using it. There's a lot of these shenanegans being played -
OneWire, SPI, I2C etc. I think that manufacturers have tried to play by
the rules and still let you know what they mean - Atmel uses the TWI -
Two wire interface that can be used with I2C

But you're right - it is annoying

Tom

tim wrote:
> I am currently working with a range of peripherals whos > control lines look remarkably like an I2C interface. > > The data sheets go into great detail about how the data and > clock line are used to communicate with the device and how > it has an own 'address' so that you can differentiate it from > other devices etc....... > > Why not just say that it's an I2C comptable device FFS. > > Do they have to pay Philips some extra money for admitting > that it's I2C rather than pretending that it is something else? > > (and is it really still in patent after 20 years?) > > sorry rant over. > > tim
<surftom@hotmail.com> skrev i meddelandet
news:1103688440.284627.4970@f14g2000cwb.googlegroups.com...
> Last I heard, I2C was a registered trademark and you had to pay Philips > for using it. There's a lot of these shenanegans being played - > OneWire, SPI, I2C etc. I think that manufacturers have tried to play by > the rules and still let you know what they mean - Atmel uses the TWI - > Two wire interface that can be used with I2C > > But you're right - it is annoying > > Tom >
Yes, you should ask Philips to adopt the TWI so we can have one standard :-) -- Best Regards, Ulf Samuelsson ulf@a-t-m-e-l.com This is a personal view which may or may not be share by my Employer Atmel Nordic AB