nRF9160-DK ECDSA v value

[Gioele]

Hello!
We are trying to sign our data using ECDSA (https://developer.nordicsemi.com/nRF_Connect_SDK/doc/latest/nrf/samples/crypto/ecdsa/README.html), so we can send our information to an Ethereum Blockchain. To send the transaction we need to obtain the "v value". Some searches made us understand that the "v value" is related to the coordinates of our "r value" so it should be 0 or 1 plus 27. Is there a way to obtain the coordinates of our "r value"? Or better, is there a way to obtain the " v value"?

Thank you very much!

[Gioele]

Let's make a recap. We need to know the correct value of "v". We need the guides and the documents that you proposed and now we know the way to obtain the proper "v". The problem is that, according to these guides, to find this value we need to see some information related to our ECDSA. For sure we need to find the coordinates of our private key. The "r value" corresponds to the coordinate "yR", we need to know for sure the coordinate "xR" that is used to obtain the sign but that we don't know how to pull out.

[dejans]

Hi,

Public key should be public. Why is it so that you do not know the public key?

Best regards,
Dejan