While an ASCII (this is a computer text version put onto a computer floppy disk) version of a document is considered an alternative format it is also the basis for braille, large print, or audio versions of a document.
You will either have to scan the document into the computer or retype the document into a computer. Scanning requires access to a scanner and optical-character-recognition software. Scanning is usually quicker than retyping, however, it does require some "cleaning up" which can add to the time required. Scanning quality also depends on the quality of the original being scanned.
Creating an ASCII version of a simple document, a syllabus for example, requires nothing more than saving the document in ASCII (sometimes referred to as "text") from a word processing program and making sure the document is single column.
More complex documents, such as multi-column newsletters, may need to be extracted from page layout programs and reformatted for ASCII presentation.