Codabar can encode the ten digits and a few special symbols (minus, plus, dollar,
colon, bar, dot). The characters "A", "B", "C" and
"D" are used to represent four different start/stop characters. The
input string to the Barcode Creator can include the start and stop characters
or not include them (in which case "A" is used as start and "B"
as stop). Start and stop characters in the input string can be either all lowercase
or all uppercase and are always printed as uppercase.
