Dot matrix printer using HTML

Hi, where can I find a list of the dynamic values that I can use … similar to {{}}
I’m trying to build an invoice that is printed using
a dot matrix printer … on pre printer invoice paper. (Only printing the fields, without the fields names)
Any help is appreciated …

You can customize the print format

The values available to print formats include all doctype variables. You can see a list of these under the Customize Form page, among other places.