My shiny new Arduino Diecimila cost US$34 plus shipping. I've gotten far enough into it to see it will be an excellent solution for a project -- if it were cordless. Let's see... an Arduino with Bluetooth will run: US$135!
And I'll need 5 of them! What am I missing? Why does a Bluetooth version cost 4 times as much? It just doesn't make sense considering I can run into Fry's and get a BT adapter for $3.99. Could an adapter be used even though it's meant to be plugged into the computer rather than a device?
Why does a Bluetooth version cost 4 times as much?
Have a look to see how much a certified bluetooth module costs.
It just doesn't make sense considering I can run into Fry's and get a BT adapter for $3.99. Could an adapter be used even though it's meant to be plugged into the computer rather than a device?
Assuming it's an USB dongle, then no, an Arduino can't act as a USB host for it.
You're saying you could use a "cordless" Arduino. Do you really need BT ? There are lots of other wireless solutions you can use, many of them being discussed in this forum.
It is not difficult to figure out...It costs that much for a number of reasons:
The BT module is one of the best on the market and does 10 times more things that most people
need but it costs a LOT
the power supply is more expensive than a silly 7805 used in the regular board
economy of scale, the number of BT boards made is a lot less than the USB , therefore some components
can't scale in price that easily
The US dollar is losing value really fast and continues to do so... anything made in europe is bound to increase in price. Thank George Bush and Ben Bernanke for that...
Some US distributors sell competing BT product so they make the price a little higher to avoid clear competition (although this was more true when the dollar was at 1.25 not 1.6 like now)
It is possible to put the board into a deadlock where the beginner user can't get out of. this leads to higher return rates..
The wiimote is 39EUR. Do you know how many wiimotes nintendo makes? MILLIONS... the economy of scale is HUGE... because of this they have the money to develop their own BT firmware and integrate it in the object itself. then they go through the very expensive process of getting all the certifications on the wireless parts.
Smaller manufacturers have to buy pre-made pre certified modules with a decent API (like iwrap)
Don't look at the 3.99USD module (It's a bit too cheap even for the US) that is made in china in billions of pieces..
also have you ever smelled a piece of cheap chinese electronics? imagine how it would be to work there 12 hours a day... then think..
BTW Honestly I dont understand some member of this community... every time somebody has to think there is some weird scheme to lock people in and milk money off them..
Look a tom igoe's book... if there was such a grand money making scheme you would see Arduino BT everywhere... all his examples use the sparkfun modules.
I mistake I made 3 years ago becomes a lock-in to sell only "special shields".. back then I made 300 boards and I paid them with my own pocket (and david cuartielles pocket) and we gave them away for free... when we asked gianluca to make the first 200 boards we didn't know if we were ever going to sell them at all... but we did it because we thought we had something there..
Now you should spend 1 hour on the parallax website asking them about the prices
I've priced Bluetooth modules for OEM applications. Buy only a few thousand and there are lots of vendors who will sell you a UART-accessible Bluetooth module, able to use all Bluetooth profiles such as audio and file transfer in addition to serial emulation, for the $20 range or lower. I agree with the first poster in this thread.
Ok in a nice collaborative project it would be more practical to say:
"Hey guys did you know that X makes module Y that they sell at Z dollars ? i'll put you in touch with them"
Unfortunately the BT boards are in demand but not in crazy demand so buying a few thousand would be a huge investement that may never pay back for whoever manufactures.
I also found cheaper BT modules but then we had lots of troubles making them work properly so...
If you want to share your info it would be good for the whole community
Making an investment is a necessary risk of going into business. This market is relatively risk-free because the product doesn't deteriorate much over time, and you are pretty much guaranteed to recover investment by selling at cost if you have to.
I've spoken with the folks at Ezurio/Laird before, but I purposefully didn't mention a specific manufacturer because there are many providers out there, and narrowing the selection right at the beginning is not always a good idea. I know that Ezurio isn't the cheapest option either.
You're saying you could use a "cordless" Arduino. Do you really need BT ? There are lots of other wireless solutions you can use, many of them being discussed in this forum.
I must not have done a very good search. Could you please provide examples? Communication to a network access point would be even more useful than BT if it didn't cost more than the card. The big thing is I need ASCII output for another program to use as input.
Please let me add it was not my intention to ruffle the feathers of any developers or pick at what appears to be old scars. Have you ever heard the saying, "If it doesn't make sense then it's probably not true?" That's how the 4xBT price struck me -- that I must not be finding the correct price/option.
I must not have done a very good search. Could you please provide examples? Communication to a network access point would be even more useful than BT if it didn't cost more than the card. The big thing is I need ASCII output for another program to use as input.
As I made the first answer, I'll answer this question too, but I won't be the most helpful on this matter, since I don't use such things myself.
But first you need to know if you want Arduino>computer wireless link with a standard protocol, which will means BT or 802.11 aka WiFi, or just Arduino>Arduino wireless communication (with maybe a last Arduino physically connected to a computer at the end)
For the first option, there are a few Wifi/BT components available, I don't know of any.
For the second option, I've often seen the name of the XBee, which uses the 2.4 Ghz band but is not a Wifi device.
To conclude, if searching returns nothing, maybe you can create a topic on Hardware/Interfacing detailing what you want to make and maybe how much you can invest in it... I'd be interested myself to know what kind of monster you're doing with five wirelessly connected Arduino
... I'd be interested myself to know what kind of monster you're doing with five wirelessly connected Arduino
I won't get deeply into details but the project involves 5 special locomotives for a model railroad. The digital command control (DCC) system that controls the engine's motor speed and direction sends its data through the rails but is transmit only (this is an international standard for DCC certification). I need the locos to report back some vary specific location information. Since the data can't return through the rails or via a cable tail that leaves some form of wireless. The ASCII data returned will be passed to a commercial DCC program that sets the loco's speed and direction. That's the high-level loop.
reality check: $135 is VERY CHEAP. Split the retail price in half to find approximate wholesale: 68.50. Subtract a ~$30 Bluetooth module and you don't have a whole lot of $ left. Compared to the alternatives, it is very reasonably priced.
Ok, so you don't really need to use wifi or bt, if the modules are too expensive. You can also use the public frequency ranges (bands ? is this English ?), using something like the XBee, and connect a sixth Arduino to the computer with the receiver, sending serial data through USB.
To save money and loose time, you can also considerer making your own PCBs using the Arduino as a programmer for some Atmega168.
You could argue that it's reasonable, but I don't think you can argue that it's "VERY CHEAP". So let's say you have a wholesale price of $68.50, and let's even go so far as to say you have to pay $30 for the bluetooth (this might not be so reasonable since you should be able to at least get the bluetooth for wholesale prices, but sure, let's go with it worst case for argument's sake). That leaves an effective wholesale price of $38 for a standard Arduino board, right? The cost of the components, PCB, and manufacturing are probably a quarter to a half of this price. If it ends up being half, the sale price is what you should reasonably expect the manufacturer to charge, but that still doesn't make the price reasonable in an absolute sense if the manufacturer is paying way too much for his components (and I'm not saying that's happening here, by the way). If it ends up being a quarter, that makes the wholesale price slightly high in my opinion.
I don't know the details so this is just speculation, but as a consumer I think I'd probably consider the board slightly overpriced for what I'd be getting. Would I still buy it? If I didn't have a better alternative solution and there was nothing else like it on the market, sure.
Just my two cents. I hope this doesn't offend anyone.
I've been looking at bluetooth for a non-arduino project, and BT is obscenely expensive if you aren't buying in mass production quantities (think wiimote).
Bluetooth is a fairly complex system, requiring a lot of engineering effort, processing power, etc.
The best I was able to find for typical arduino-level hobbyist use was about US$60 per module. The Arduino BT isn't really out of line, price-wise, with what I found in my own research.
To the original poster: XBee may be had cheaper (I don't know, it's worth a look). BT, as implemented in the Arduino BT, may not even work in a network as you describe, because all of the obscenely expensive BT modules I found were only able to support a single SPP connection (even though the bluetooth protocol allows 60-something).
Yes the risk of buying 2000 modules is part of what a manufacturer should take on... It would be interesting to find a US manufacturer willing to take on that risk.
The Module used in the Arduino BT is expensive also because you can make it do anything (almost)
You can handle 7 concurrent connections using an "API mode" and you can create scatternets, i.e. networks of more than 7 devices.
There is a very ingenious hungarian guy who configure it as a bluetooth headset and used it to turn a rotary phone into a mobile phone heaset.
Next year they promised the firmware will do HID as well which means mouse/keyboard emulation
reality check: $135 is VERY CHEAP. Split the retail price in half to find approximate wholesale: 68.50. Subtract a ~$30 Bluetooth module and you don't have a whole lot of $ left. Compared to the alternatives, it is very reasonably priced.
To be clear, I don't think the BT is overpriced in the sense that I don't think anyone is making that much profit on it. And from what I understand, the retail markup is nowhere near 50% (otherwise you'd see someone buy 100 for $68.50 each and sell them on eBay for $100 each).
But, while it really does cost them $135 to get this product into the market, when you compare it with what's available in the computer world, $135 is not very cheap for what you get.
If the Arduino team's choice is to make it available for $135 or not even attempt to offer it, I applaud them for making the option available.
