Problem:

Listed in the range A2:B7 are characters and their corresponding ASCII codes.
Note that upper and lower case forms of the same letter are assigned different codes.
We want to be able to find the code from cells B2:B7 that provides a case-sensitive match for each character in cells A11:A13.

Solution:

Use the INDEX, MATCH, and EXACT functions as shown in the following Array formula:
{=INDEX($B$2:$B$7,MATCH(TRUE,EXACT(A11,$A$2:$A$7),0))}