Hi Howard,

It may be that the operating system is displaying the Hexadecimal number for 10... Hexadecimal notation (Hex) is often used in computer based instruments and their software.
In hexadecimal notation you have 0,1,2,3,4,5,6,7,8,9,a,b,c,d,e,f representing the decimal values of 0 to 15.

So hexadecimal 'a' is equivalent to 10 Decimal : 'b' = 11 etc.
Hex is usually written in lower case letters, but can also be written in upper case.