Interactive Workflow

This is not a project tutorial. It is the workflow tutorial.

Froth work is a loop: send a small change, run it on the target, inspect the image, and revise the same names. The board is not just where the final program runs. During live work, the board is the development environment.

Keep The Change Small

Start with one helper:

to dot with x, y [
  grid.clear:;
  grid.set: x, y, true;
  grid.show:
]

Run it:

dot: 2, 2

If the display is connected and initialized, one pixel should light.

Use A Named Entry Point

Give yourself one command to rerun:

demo.run is fn [
  matrix.init:;
  matrix.brightness!: 1;
  dot: 2, 2
]

Now the edit loop has a stable handle:

demo.run:

Change dot, then run demo.run: again. The entry point resolves the current value in the dot slot, not a stale copy.

That single fact changes the way you should work. Do not write a twenty-line definition and hope. Write one small word, test it, and compose upward.

to line.demo [
  grid.clear:;
  matrix.line: 0, 0, 11, 7, true;
  grid.show:
]

Send that. Run it. Then decide whether the next word should draw a box, read a knob, or change brightness.

Inspect The Image

Use the same names the editor calls:

words
show @demo.run
see @dot
info @matrix.init

Inspection is part of normal work. It tells you what the image currently holds.

Use words when you forgot a name. Use show or see when the name exists but the behavior is not what you expected. Use info when you need to know whether a binding is foreign, base-image, user-created, or persistable.

Interrupt A Bad Loop

If you start a loop that runs too long:

repeat 1000000 [
  demo.run:;
  ms: 20
]

Press Ctrl-C at the prompt or use Froth: Interrupt in the editor. The runtime checks for interrupts at safe points and returns to a usable prompt.

In VS Code, Froth: Interrupt sends the same kind of interruption through the connected control session.

Save The Session

When the current overlay is worth keeping:

save

Reboot, reconnect, and inspect the names again. The base image is rebuilt at boot, then the saved overlay is restored on top.

If you save a bad overlay, use restore only when the saved image is known good. Use dangerous.wipe when the saved overlay itself is the thing you need to discard.