How to calculate the check character of JDC?

[jinpeng1989]

The last character in the Joining Device Credential is a check character. The check character is generated using the Verhoeff algorithm.
OpenThread supports verhoeff calculate CLI, but the input string MUST consist of characters in ['0'-'9'].
The character set of JDC not only includes ['0'-'9'], but also 22 capital letters. How to use the CLI to calculate the check character of JDC?
Are there any other tools available for calculation? Could you share them with us?

[abtink]

OpenThread provides the Verhoeff CLI/API for Border Agent's Ephemeral Key use case (Thread Administration One-Time Passcode) where the input is restricted to [0-9].

You can find a variety of Verhoeff algorithm implementations with a Google search.

Alternatively, you can contribute a pull request to OpenThread to expand the scope of the provided Verhoeff APIs to support other inputs.

[jinpeng1989]

Thank you.
For the Verhoeff algorithm of the check character of JDC, what should the definition of the permutation and the multiplication be? Based on the description in the Thread specification, I don't know how to define them. Could you offer any assistance?