Is that why nobody uses it anymore? Only thing I know about it is that it used stack like expressions. (kinda like RPN but for everything)
https://www.forth.com/embedded/#Annotated_example_source_cod... contains a version of the canonical washing machine program.
\ Top-level control
: WASHER ( -- ) WASH SPIN RINSE SPIN ;
You can then look at the definitions for 'WASH' and 'SPIN' and 'RINSE' and so on until you get down to what IO bits you're turning on or reading when and for how long.