Slashdot Mirror

What's even better architecturally is to NOT use lossy compression on the stream (or do so a second time, in the case of already compressed audio). And even better, architecturally, for those who watch videos on the phone is to NOT use a connection scheme that has 100 to 200 msec of latency. Unless you like having all your videos look like poorly dubbed Hong Kong kung fu movies from the 1970s...

Having half an ohm of impedance between your amp and a 32-50 Ohm driver is pretty irrelevant, comparatively... Oh - and EQ can still be applied, as the effect of that cable impedance is essentially the same as higher amplifier output impedance - it's a completely predictable "filter" on the system and can easily be dialed out as needed (not that it is needed, in 99% of all cases).

Lastly, a typical headphone transducer consumes less than 1mW of power (they are typically 95-105 dB SPL @ 1 mW output). A Bluetooth radio typically consumes 30-40 mW when operating - quite a bit MORE power is consumed by a Bluetooth radio than a headphone amplifier. So using a Bluetooth headphone will dramatically increase power consumption relative to a wired headphone.

Aptx? Oh, you mean that CODEC that was developed in the 1980s, and is currently a Proprietary CODEC owned and commercialized by CSR, Inc. (now owned by Qualcomm)?

Yeah, that's REALLY "moving toward the future".

Actually, SE get their Bluetooth from Cambridge Silicon Radio. As do Nokia, for some of their newer devices.

And pretty much everyone making something with Bluetooth in it is buying fron CSR (unless they are making it themselves).

Interesting, how often I will hear this, when I mention about my mouse... this is just some sort of anti-MS FUD (not that I like MS, but I neither like any kind of FUD). They didn't just make drivers for Macs, but the mouse itself does follow the BT spec - and it must follow, as their own BT dongle has a standard CSR chip onboard. I've actually used the dongle W2k with 3rd party drivers (but not with mouse - W2k does not support BT HID's), although MS itself only provides drivers for WXP.

Hell, a friend of mine who is a BlueZ developer made it work under Debian with his iBook, and he said it was not any great hassle. The mouse is just in undiscoverable mode by default - you have to press the connect channel button at the bottom of the mouse to make it to be discoverable for a moment to pair it with your box. What MS has crippled, is the setup of the mouse under WXP, which does not require pressing that button, but still finds the mouse.

The support was added in OS 10.2.5, and Apple also has an article how to make it work (and another for keyboard).

SCO is the Synchronous and Connection Oriented physical link which transports voice across a Bluetooth link.

Source

I'm doing some work with Bluetooth, using the CSR modules, "Casira" programmer, and the Bluecore programming tools. For simple stuff like headsets and RS232 links, you can run all the necessary code on the module.

For stuff based on CSR silicon, if I were doing things over, I'd go with the Siemens dev kit for their Siemo or Siemo2 modules. Same tools, more or less, but you're working with modules right away that you can spec into a final product. I didn't find them until I was looking for prequalified modules based on CSR's chipset...

You are completely right about mixed signal chips being a reality for a long time: you don't need to look any further than a video card in your computer to see that. Intel mentions "silicon radio" as if it is a new idea, but a company already exists called Cambridge Silicon Radio, so you can see it isn't just Intel in this business.

I have a feeling that something important is being left out of this article. If you look at the original press release you see that it is a total mishmash of different Intel developments. The poor journalist was stuck trying to find a lead in this story (other than "Intel has bunches o' innovation") and zeroed in on the part that mentioned Moore's law, which he had heard before.

The most interesting part that I see is the tunable laser using silicon photonics. Si has an indirect band-gap, which makes it not very good for making lasers and optical devices. That could be big news.

Cambridge Silicon Radio is saying that they will ship their new chip at about $5 sometime this year.

It sounds to me like SPIKE will be the real follow-on replacement for IR (IrDA) and that it will actually bring us the kind of connectivity which was promised there but never delivered (well, maybe it was delivered but it was rarely used).

Bluetooth (tm) brings us a different kind of connectivity for a different purpose and it looks to me like they both have a place, as do Wi-Fi (802.11b) and CDMA/GPRS/UMTS. [ a place for everything and everything in its place ]

I am certain that many technologies will be mis-used in the future and I am sure that some people will be very happy about that and others less happy. We have seen lots of examples over the years (beta-max/vhs; Linux/MacOS/Unix/Windows; [give me a command line and get out of my way])

I have no doubt that we will see Wireless LAN's built using Bluetooth (tm) and that someone will add Service Discovery to some 802.11(b/a/g/e) implementation. It will not matter to consumers whether those are mis-applications of the technology.

What will matter to them is:

What do I find on the store shelf when I go looking for a solution?
Does it work how I think it should work?
Is it easy to use, easy to set up, etc?
Did my favorite super-model or football player tell me to buy it?

Bill Austin
Bluetooth (tm) Mailing List
Top Bluetooth (tm) Sites