LEDs

H1 has a single onboard status LED, and it’s fully under your script’s control rather than tied to a fixed meaning:

LED_ON / LED_OFF — turn the LED solidly on or off from your script.
Custom blink patterns — combine LED_ON, LED_OFF and DELAY instructions to build your own pattern, for example to prompt for input or signal that a script is about to finish.

blink.hdc


LED_ON
DELAY 300
LED_OFF
DELAY 300

If you’d rather your script run silently, just leave the LED off — H1 doesn’t force any indicator behavior on you.

See LED commands in the language reference for the full syntax.