In part 1, I talked about how to get FIG-Forth for the IBM PC running on PCjs. FIG-Forth was a popular and very compact, public-domain version of the medium speed Forth systems programming language and environment during the early 1980s. Then part 2 covers how to implement a very rudimentary disk-based editor as a precursor to an interactive full-screen editor.
It would be possible to implement a full-screen editor entirely using the existing word set, if it provided definitions that could control the position of the cursor on the screen and the ability to clear the screen.
Unfortunately, it's not possible to do that either by sending display control codes via EMIT, nor via any other special commands. EMIT does support some control codes, carriage return is 13 EMIT, backspace is 8 EMIT, cursor right is 9 EMIT and cursor down is 10 EMIT.
The rest just produce graphics characters.
Let's Do Some Machine Code!
DEFINER CODE DOES> CALL ;CODE Noop 253 C, 233 C,
' NOOP CFA @