Simple dual button bluetooth device with on/off switch, development advice - bluetooth

Hoping someone can point me in the right direction as I need to develop a simple 2 button bluetooth device that acts as a 2 character keyboard when paired.
( tried repurposing camera shutter devices but to no avail).
What would be teh best suggested development system and chipset for such a simple device ?
Thanks
Alan

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Bluetooth extender to control outdoor Bluetooth LED light Strips

I have outdoor LED strips that are bluetooth controlled, Govee ones. I presently have to go to different regions in the house to turn them on and off from my phone via bluetooth connecttion to the light strips, all 5 individually. Is there a bluetooth range extender I can get to have better coverage to the LED strips? I see range extenders, but they are all for audio, I am just looking to have better access to the strips. Any product if it exists to help for this would be much appreciated, thanks
Reno
Tried connecting locally, no problem but need to go somewhat close. Found some bluetooth extenders, but they are geared for audio

Use STM32 as a mouse and keyboard

I finished using Stm32 as a mouse and keyboard one by one but I don't know how to combine both at the same time. I followed this guide https://damogranlabs.com/2016/03/stm32-custom-usb-hid-device-yes-please/ but what should I change in usbd_hid_core.c?
Any help would be greatly appreciated and if anyone has questions about setting up a mouse or keyboard, I would be happy to answer.
This can be done in two ways:
Make a so called USB composite device with two functions - one mouse, another keyboard. Google for examples om GitHub an other places.
Pure HID implementation. Each function will be a so called HID collection. You'll need to create a HID report descriptor with two (or more) top level collections.
With this approach, USB composite stuff is not needed, the device can have only one function. This is much simpler than composite design, with less resources. But some old computers or host devices don't understand HID collections.

How do i take input from a usb keyboard to arduino uno

I am trying to do USB keyboard interfacing with arduino UNO. I would like to take input in the form of ascii values. How can i do it?
Thank you for answering my question. But i figured it out that we could use a female USB connector and connect the data pins with the pwm pins and further use the PS2Keyboard.h library to read input.
The newer 32u4-based Arduino boards (such as Leonardo) support a native Mouse and/or Keyboard integration. For the Arduino Uno you will need extra libraries/firmware to realize a HID keyboard. You can find several approaches and libraries on the web (e.g. Arduino HID Project 2.2, Turning an Arduino into a USB keyboard and so on. Search "Arduino Uno as HID keyboard").

Stacked shield doesn't have enough power -- dim PWR light

I'm stacking a SeeedStudio Bluetooth Shield on top of a Olimex EKG/EMG Shield.
At first, I stacked the two loading only bluetooth shield demo code and all the LEDs lit up brightly and worked fine.
Now (having only taken a shield off and put it back on), the lower shield's (Olimex) power LED appears dim and the upper shield (Bluetooth) is not powered at all. The lower shield's power LED brightens when I remove the top shield.
Not sure what happened here -- both shields work perfectly if they are the ONLY shield on top of the Arduino. Is there any way for me to check the output voltage coming from the lower shield (Olimex) to the higher shield (Bluetooth) with a multimeter to see if it's sufficient (3.3V)?
Looks like you may really have a current problem.
Your Bluetooth shield can draw up to 100 mA and it is 3.3 V.
Your Olimex shield does not have details about the power but even assuming 20 to 30 mA, looks like you do not have enough current from the Arduino 3.3 V which is limited to 50 mA.
The easiest solution would be to use an Arduino bluetooth shield instead of the actual one, which would be 5V instead of 3.3 V and then you solve the problem of the current limitation for both the Olimex and the bluetooth connecting the Olimex jumper to the 5V and the bluetooth on top.
Alternatively, you can try to use a level shifter for the bluetooth on top of the Olimex. Slightly more complex but would allow you to use the 5V and save the actual bluetooth.

can bluetooth low energy be used like nfc - say printed to an ID badge?

I'm using my iPhone to scan in a complex 2D barcode. Problem is, the iPhone camera doesn't do so well at very close distances (less than 3 inches).
I was wondering if there were a way I could affix a Bluetooth low energy "sticker" to a piece of paper. The idea being instead of using the camera to scan a 2D barcode, I could just put my iPhone near the paper and "scan" it.
I'm extremely new to Bluetooth tech, so it's quite possible that what I'm asking for is completely ridiculous. Please forgive me, if that is the case.
Unlike NFC, Bluetooth Low-Energy devices need a power source, so it's imposible to just "print" them. They need a BLE chip and a battery to operate. So while you could use BLE same way you use NFC (proximity-based actions), you won't be able to do it with just a sticker.
Register at bluetooth sig for manufactorer id. Then put manufacturer id in advertisement package 0xff with id (16 bit) followed by the data. You must be sure your length is correct or iOS can't decode it.
For NFC, your scanner must be pretty close to the tag. But BLE devices work within several tens of meters without any problem. This is like an active RFID chip.
Of course, you need a power source for it. But if you print this BLE tag to a piece of expensive equipment, the cost of the tag and the battery is not a problem. You can use a button cell battery to power the BLE tag up. Let is broadcast/advertise some info once a second. Of course, you have to add some security mechanism if you want to be away from any replay attacks.

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