Question: what are the main functions of the control bus
[{'answer': 'carries commands from the CPU', 'provenance': [{'wikipedia_id': '2886487', 'title': 'Control bus', 'start_paragraph_id': 2, 'start_character': 285, 'end_paragraph_id': 2, 'end_character': 314, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'answer': 'returns status signals from the devices'}, {'answer': 'communicating with other devices within the computer'}, {'provenance': [{'wikipedia_id': '2886487', 'title': 'Control bus', 'start_paragraph_id': 2, 'start_character': 0, 'end_paragraph_id': 2, 'end_character': 486, 'bleu_score': 0.9434935356067541, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 3213097818608329119}, 'section': 'Section::::Abstract.'}]}]