Thai character data procedure

Thai character data string uses the following format:

Base character, <Below character >, <Above character>, <Top character>, Base character, ……

The printer checks whether the received character is the Base character. If the Top, Above, Below characters are sent before the Base character, these characters are ignored.

After receiving the Base character, the printer checks the next character until it receives the next Base character.

If next character is the Below character, the Above character or Top character, the NCR 7199 Series printer checks whether these Thai characters are valid for the current Base character. If valid, the NCR 7199 Series printer merges the characters images on the Base character image. If invalid, the characters are ignored.