"Count your blessings -- or not! For many years I carried a card in my wallet with a table in it, 16 columns and 16 rows, with which I could determine the printable character represented by an 8-bit code, or vice versa, the 8-bit code for a character. I even used it fairly often -- in the good old days." I used to have a program that allowed me to scan through the data recorded on a programmable chip. I used it to scan for the character set.
At the time, I could program chips myself, and it was fun to do modifications to the character set.