VBA calculate checksum xor of string

Hello everybody,

Let me first wish you all the best and every success for 2021. Here is my problem.

Given an alphanumeric string, whatever length of said string, say 1 up to X<20 characters, whatever number of strings in a selected excel spreadsheet column, I need to :

1. calculate the checksum xor of each string, based on ascii value of each character of the string,
2. convert xor calculated checksum value into hexadecimal, making sure that the hex checksum is a 2-digit string : if the hex conversion returns only one digit hex checksum, add a zero ("0") before the cheksum value),
3. concatenate said hex 2-digit checksum with the corresponding string in some adjacent column.

I have used scadacore checksum online calculator to obtain the correct ascii based xor values.

Anyway I am grateful for any feedback, again thank you in advance for your advices.

BR