Cheap bluetooth for arduino?

Thread Starter


Joined Apr 17, 2012
Once again I'm cannibalizing parts to try to save money...

I'd really like a bluetooth adapter to use with my attiny but I don't want to spend $50.

I have an old trendnet TBW-101UB (v3 the non see through case ones) that I bought for less than $20 originally. I took it apart and it has a nice little
general purpose chip on it a BCM2045. I found a very meager datasheet here, , according to which among PCM and USB interfaces, it also has an SPI interface on it. Well it runs off 5V (at least the 5v support is on the board if not) and has SPI :D. unfortunately I have not found a more detailed datasheet on it. Could anyone help me find it, or point me in the direction of a very cheap serial to bluetooth or otherwise something usable with an arduino. I do have an other better bt adapter, might try taking it apart and see whats in that.

This could benefit a more people though, if we could find a cheap usb adapter with a decent chip in it that can be repurposed relatively easily. These adapters are a lot cheaper than any arduino or other kit I found so far.

Have you looked at RS Components SPI Bluetooth transcievers at less than £3.00 each?
Part # is 731-2805. I have a couple hooked up to Atmel 32M chips, but I haven't used them with any Arduino based boards yet.
I have a prototype pair to make for a small engineering project, which if successful will be miniaturised to fingernail size - so the bluetooth will sit like a sanwich on-top of the CPU board.

Prototyping is easy. Miniaturising is less so as i don't have flow soldering or SMD practical experience and am a bit heavy handed with my soldering iron at the best of times - being more used to through-hole components.

Let me know what you reckon to them. Datasheets are available on RS website.

Best of luck,

Markus Sparkus:)


Joined Oct 25, 2010
Hope no one thinks I'm hi-jacking?! Markus, I'd looked at the data sheet for those modules, how did you get on with them? Do you know if they can be used to send serial bluetooth data to a phone? I've got a few of the serial ones you can get from ebay sending data from a pic to my phone, I'd like a more reliable supply than ebay though and they are sooo cheap! I couldn't see any mention in the datasheet of the long bluetooth address used by mobile stuff though?
Cheers Geoff