I am trying to connect a Wahoo Scale 1.3 to read the live weight of a person via bluetooth notifications.
The live weight can be read via the following characteristic:
handle: 0x0025, char properties: 0x10, char value handle: 0x0026, uuid: 00002b01-0000-1000-8000-00805f9b34fb.
This is working with LightBlue app on my iPhone.
When I try to receive notifications via gatttool I get the following error:
Command line gatttool: (tried also lots of different notations from different stack overflow topics)
[XX:XX:XX:XX:XX:XX][LE]> char-write-req 0x0026 0100
Error: Characteristic Write Request failed: Attribute can't be written
btmon bluetooth log
< ACL Data TX: Handle 0 flags 0x00 dlen 9 [hci0] 4.291021
ATT: Write Request (0x12) len 4
Handle: 0x0026
Data: 0100
> HCI Event: Number of Completed Packets (0x13) plen 5 [hci0] 4.327199
Num handles: 1
Handle: 0
Count: 1
> ACL Data RX: Handle 0 flags 0x02 dlen 9 [hci0] 4.383580
ATT: Error Response (0x01) len 4
Write Request (0x12)
Handle: 0x0026
Error: Write Not Permitted (0x03)
One thing I noticed is that under UUID 1901 (weight service) there are 3 properties: 1: write/indicate, 2: notify, 3: notify. Bluetooth characteristics on LightBlue App
I am able to write with gatttool to the first property, but not to the 2 and 3 property. But how does LightBlue starts listening for notifications?
I tried this one two different systems: Beaglebone Black with QN9021 BLE controller (Bluez 5.38, OpenWrt Linux 4.4) Beaglebone Black WiFi/Bluetooth (Bluez 5.23, Debian Linux 4.4)
Do I get this error because of incompatiblities of the Bluez stack and the Wahoo Scale? How do I fix this?
Thank you!
