Convert TEXT to ASCII

text to ascii conversion most likely represents changing of encoding of text file that can be done with various HTML/text editors, for example between UTF-7 and UTF-8, which actually are both extended versions of ASCII and backward compatible to original ASCII. You can usually change the encoding of your file with "Save with encoding" function that can be found in pretty much any decent text editor like Sublime text.

Another possibility, albeit very rare would be conversion of text to ASCII number format, which is doable with special text converters, like ABC Amber Text Converter.