SendData fuctions return true, but characteristics value is not changed

[Bhavesh Shah]

I am trying to make a custom application in which I need to connect to a device and read/write its characteristics' value. But my target device has had 4 primary services. And I am not able to write to its any characteristics. SendData function is returning true. but when I try to read that characteristic value it shows it is not changed.

I am able to connect and read write with other BLE devices with the single primary service.

But not able to write on over a target BLE device with 4 primary servicesIs there anything that needs to be taken care writing the value in service in a characteristic.
Can any one suggest me how to resolve this problem? I need to read/write few characteristics from many characteristics. Do I need to define all the Services and their char. and create their respective pipes ?

[endnode]

"SendData" is function where??? "I try to read the characteristic" how? From the firmware running on nRF5x side on top of Nordic stack (soft Device) through SD API? Or over the BLE for some GATT Client? "other BLE devices" means what? What is your actual set-up and what are "others"?

So firstly you need to carefully describe your system so we can understand it. What HW do you ue, what software/OS/app/FW you run on it, if some of them is Nordic device then what exact BLE stack you use and where you go the FW (= is it some example from nRF5 SDK which you haven't modified or is it something completely different?), what do you do with the devices, what you expect to happen and what happened instead.