STRING also has two subtypes, just like CHAR. The old, “old-school” STRING, which describes the text with ASCII characters, and WSTRING, which uses WCHAR characters with two bytes per character. Both types are suitable for storing text, which can be extremely useful for communication, especially in HMI connections.

For both types, the first two positions show the maximum length of the given STRING and the current filled length. One position equals one byte for STRING, and one word for WSTRING.