Lesson 4 — OR Stop

Briefing

The simulator exposes two active-high stop commands: each tag is FALSE while released and TRUE while pressed. Use two normally-closed (negated) logic instructions in series so either command turns the lamp off. This is a Boolean-logic exercise, not a safety-circuit design. Physical NC stop circuits use different healthy-state input semantics and require suitable devices, monitoring, architecture, and validation.

Objectives

• LAMP is ON when neither STOP_1 nor STOP_2 is pressed
• LAMP goes OFF when STOP_1 is pressed
• LAMP goes OFF when STOP_2 is pressed

I/O Table

Your program will be tested against:

All test cases run automatically when you submit. Assertions are hidden until you pass.

1. #1Neither stop pressed → LAMP on

   Both active-high stop commands are false, so both negated instructions pass

2. #2STOP_1 pressed → LAMP off

   One stop breaks the series chain

3. #3STOP_2 pressed → LAMP off

   Other stop also breaks the chain