Your question is OS, Volatile, and Code Reading. Take a moment with it on the right.
Talk me through your thinking if you like. When you're confident, submit your answer and I'll grade it like a real screen (7/10 or better passes).
In a Qinetiq embedded-systems interview, the panel asks about your OS experience, then hands you two short snippets cold: one C, one Python.
volatile uint8_t sensor_ready = 0;
void ISR_SensorDataReady(void) {
sensor_ready = 1;
}
void wait_for_sensor(void) {
while (sensor_ready == 0) {
// spin
}
sensor_ready = 0;
process_sensor_data();
}
def flatten(nested):
result = []
for item in nested:
if isinstance(item, list):
result.extend(flatten(item))
else:
result.append(item)
return result
print(flatten([1, [2, 3, [4, 5]], 6]))
First, briefly describe an embedded OS you've worked with (RTOS or otherwise) and what it was used for. Then explain what the volatile keyword means in C and why it matters for sensor_ready specifically. Finally, explain what the C code and the Python snippet each do.