Convert base 10 number to null terminated ascii string

I'm wondering if I am thinking about this correctly. I need to convert 301 base 10 to a null terminated ASCII string in hexadecimal.

I get the following:

3 = 33 0 = 30 1 = 31 NULL = 00

Which would look like 33 30 31 00 as a null terminated ASCII string in base 16?

I appreciate any feedback.