I need to provide communication via Bluetooth Low Energy 4.0 between iOS-device from one side and certain peripheral device, which has bluetooth-module onboard.
Peripheral device was assembled with DORJI DBM01 bluetooth LE 4.0 module which allow to communicate with it using one characteristic with READ property (UUID = 0xFFF4) and one characteristic with WRITE property (UUID = 0xFFF1). Technical manual of DORJI DBM01 is here: http://dorji.com/docs/data/DBM01.pdf
I succeeded in establishing bluetooth LE connection between iOS-device (using Core Bluetooth Framework) and described above peripheral device, but characteristic with READ property doesn't have a property of notify (CBCharacteristicPropertyNotify in Core Bluetooth Framework).
So I have to use some kind of infinite loop to scan and read new information from characteristic with READ property (by calling method of CBPeripheral instance - readValueForCharacteristic:) instead of subscribing to a characteristing value (by calling method setNotifyValue:forCharacteristic:).
Is it possible to add notify property to read characteristic of peripheral device (for instance, by engineer who built peripheral device or adding some low-level code which run on peripheral device) or notify property is an integral part of BLE-module (DORJI DBM01) and it can't be added without using another BLE-module?
1 Answers
The DBM01 is based on a Texas Instruments CC2540, like many other BLE-to-serial modules, which do implement notifications, so technically, it is definitely possible to do it.
However, this requires the firmware of the DBM01 to support it, and you'll of course have the issue of upgrading said firmware in existing modules. Unless there are undocumented features on the module, I doubt there would be a way to change the behaviour of the module without touching the firmware.
Another option could be (but that really depends on your scenario) to switch the central and peripheral roles, so that the iOS app would be notified when the BLE module writes data. As I understand it, this needs to be done in hardware (the level on a specific pin needs to be changed).
