We noticed in the AICC code in SCORM Driver that it converts many foreign language characters to underline characters in putInteraction commands of learner quiz answers to the LMS.
I'm trying to understand what gets converted. Do you just send the 128 basic ASCII characters(ISO-8859) as is and then convert the rest?
Is there a definitive list of what exact characters are sent "as is" for AICC and SCORM?
Your understanding is correct. ASCII characters are sent through, but others are just replaced by an underscore.
Responses may contain only the following characters, - ( ) + . : = @ ; $ _ ! * ' %. If anything else is found, it is replaced by '_'.