Hello,

I am using mbed TLS on siliconlab microcontroller. I am using Openssl on android for Ecdh implementation and mbed TLS for the microcontroller.

On Android, i am able to calculate Ecdh shared Secret using X and Y coordinates of the curve generated by mbed TLS.

But on mbed TLS I am not able to calculate Ecdh shared Secret using the X and Y coordinates sent from android.

I am concatenating the X and Y and pass the buffer to the following function:

mbedtls_ecdh_read_public(&ecdhContext, concatinatedArray, 58);

but it returns error code .

1- Is there any simple way i can use the X and Y coordinates to calculate the Ecdh shared secret?

2- Is there any example that works with openSsl Ecdh?

3- How i can generate/ calculate public key from the X and Y coordinates?

```
I used the following function to get the public key:
```

mbedtls_ecp_point_read_binary(&ecpGroup, &ecpPoint, concatinatedArray.dataPtr, (size_t)concatinatedArray.dataLength);

but it is not correct.

*mbedtls_ecdh_compute_shared* gives error **MBEDTLS_ERR_ECP_INVALID_KEY**

I will be really thankful for your kind help.

Regards