Bluetooth BLE to another Bluetooth BLE or 2.

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Wayne

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Alrighty then,

Next project is to use BT between 1 master (receiver BT ) to 2 slaves BT (I guess thats what they are called)
The logic is switch closures sent BT to the receiver that will produce a closed (relay contact) for some buttons. Some will close as well but with another relay as security or action.
Some will work in 2 steps. These are ARM and X-Ray.

We have a product out, but the cost of batteries is high, they do not last because of high current (Used in a handset and footswitch)
The receiver gets power from the system ~5vdc or 24vdc (depending on systems)

Long ago I did help with the 1st gen of this product, since it was outsource to some other engineers. Now they have requested me to look into it.

The request is lower battery power (3vdc to 4vdc) using Alkaline off the shelf. They want to have it last a long time .. Currently we suggest to recharge daily. Long time is for months. So BLE with sleep etc.
Hoping to have exchange of the piece of the product. Currently if the footswitch is bad, we need all pieces (Footswitch, Handset, and receiver) So pairing by customer is needed.
Limited range. Since the doctor has the device, he needs not to be far far away. Out current unit will engage x-ray 100's of feet away.. Not needed.

I got the request late last week, so fairly new. The pairing I have an idea, but what to do is another. I'm sure Master and Slave is correct.

So Teensy to control BT (BLE type)
Paul, I'm sure you been getting orders for the one IC.

I think I better change the design on that current product that we use it on (2 boards, 3 IC's total each)
But back to this.

Suggestions on BT modules will be great. Low current ones.. I will look into sources, I have sent email to Pycom and u-blox. ublox has started.

Not a small qty, something like 800 BT modules or more / year.
I have lost count on the IC's bought from Paul so far.

Wayne

Excuse the confusing post.. Back from Vacation and got in late..
 
Well, from research and other BT BLE forums, be trying out a few.. RFduino, Simblee, WiPy's and puck.js's units. Should have that all this week.
 
Ok, I see adding a BT to a teensy probably not the way to go.. I just love the teensy so much..

But I have tried a few.. puck.js (Programs via BT (OTA)).
RFDuino. Bout 1, sould of gotten 2..
Simblee.. Sould connect to the above, not yet, but this unit is good so far..
Pycom's WiPy still in transit..

All the above have about 30 GPIO's with other stuff. So far the Simblee is the smallest.

I have a simple program on the SEND device and the RECEIVE device lighting LEDS. I think I might give it a go by typing the connections onto a existing PCA and test.
 
It's probably possible but it would be a bit challenging. If you've used the Snooze library you could probably get it to do the low power stuff. I've successfully used classic BT with the Teensy running at 2MHz. Does the unit need to always be on, or can it be turned off when not in use?

If you don't go with the teensy, I'd suggest looking at the nrf51 or nrf52. They have example code for most basic scenarios and are pretty easy to get up and running. They've recently updated the BLE firmware to even do mesh networks.
 
I feel like a traitor .... there is an excellent SAMD based solution from adafruit.... its called the feather M0 bluefruit LE or some such. Adafruit feathers and teensy's are close cousins ...Anyway the feather has a nRF51 (or is it 52?) Nordic ble module wired into the spi port ...and adafruit have done a really excellent job providing programming infrastructure. As for using it as a master, I haven't done that, and I don't know whether adafruit provide software support for it.....I think they only use a slave Nordic 'softdevice' ...I'm not sure about that, though. I think you could put your own master-capable soft device on there if you wanted..... There is also the readbear nano ....I'm pretty sure that has a full master/client softdevice stack on there, and it is probably easier to put one on there if not... the thing is, programming a nRF51 is not a trivial task, even with all of the sdk support from Nordic....I guess you know that.
 
I saw the Adafruit device also (it has a Cortex M4F in it with hardware floating point). I was thinking of doing some radio stuff between Teensys, and I got the SPI bluetooth boards, but I haven't wired them up just yet.

After getting the boards, I read the Adafruit FAQ: https://learn.adafruit.com/introducing-the-adafruit-bluefruit-le-uart-friend/faq#faq-2 which says:

Can my Bluefruit LE module connect to other Bluefruit LE peripherals?

No, the Bluefruit LE firmware from Adafruit is currently peripheral only, and doesn't run in Central mode, which would cause the module to behave similar to your mobile phone or BLE enabled laptop.

At some point we might consider a new firmware image offering this, but since 98% of the uses cases for BLE involved running as a peripheral we've concentrated all of our development effort there for now.
Click to expand...

So, I will consider it for stuff pairing with a phone, but it doesn't seem to do Teensy to Teensy.
 
MichaelMeissner said:
I saw the Adafruit device also (it has a Cortex M4F in it with hardware floating point). I was thinking of doing some radio stuff between Teensys, and I got the SPI bluetooth boards, but I haven't wired them up just yet.

After getting the boards, I read the Adafruit FAQ: https://learn.adafruit.com/introducing-the-adafruit-bluefruit-le-uart-friend/faq#faq-2 which says:



So, I will consider it for stuff pairing with a phone, but it doesn't seem to do Teensy to Teensy.
Click to expand...

There you go ... no master...you need the right nordic softdevice for master / central ... s120 ...certainly not impossible to put onto the feather, I am guessing, although maybe you have to use the swd port or something??? Not sure how you would do it over the spi interface, but I guess there is a way ......programming the nordic piece is not easy though...there is a lot to it. Maybe try putting s120 onto the redbear nano might be easier ...

I'm sure you know about Hc05 ...I have a pair (old school bluetooth) ..they work flawlessly !! Sending serial messages backwards and forwards between two teensys ... not low energy!

BTW the feather works perfectly as a slave, sending ble midi to a computer....the adafruit midi protocol for bluetooth is perfection itself...
 
Well, as it turns out I'm ending up using the Simblee's. Works using SimbleeCOM and has ULP. In ULP, wake on button option, its is around 1ma sleep and 14ma -16ma send (depends what power I want to use).
I understand new libraries are on the way, so maybe some added features maybe coming.

So the puck.js are to easy to read from BT, using dump command you can retrieve the code (security issue so far).
PyCom stuff could be ok, but it took weeks to get and I see little support.

The Simblees devices have 29 IO or 30 IO pins. This is the one feature that I like!

With the use of SimbleeCOM, I can have I think upto 8 devices (Unlimited in COM, 8 in BLE) to 1 host. No need to give names to any of the devices either. Als,o you can not see the Simblees when in SimbleeCOM, they only link to each other using SimbleeCOM option.
These can also be set to close range to work from a few inches away and up.
 
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