Six statements are given about methods of data transmission. Tick (✔) to show if each statement applies to serial simplex, parallel simplex, parallel half-duplex or serial duplex data transmission. Some statements may apply to more than one data transmission method. Statement Serial simplex (✔) Parallel simplex (✔) Parallel half-duplex (✔) Serial duplex (✔) bits are transmitted along a single wire data is transmitted in both directions it is only suitable for distances less than 5 metres bits from the same byte are transmitted one after the other data may not arrive in the correct sequence data is transmitted in both directions, but only one direction at a time

Mark scheme

Marking points from the official mark scheme (Oct/Nov 2021). The mark or mark type is shown in brackets.

1. 3(a) One mark per each correct row. Statement | Serial simplex (✓) | Parallel simplex (√) | Parallel half-duplex (√) | Serial duplex (✔) ------------------------------|--------------------|----------------------|--------------------------|------------------ bits are transmitted along a single wire | ✓ | | | ✓ data is transmitted in both directions | | | ✓ | ✓ it is only suitable for distances less than 5 metres | | ✓ | ✓ | bits from the same byte are transmitted one after the other | ✓ | | | ✓ data may not arrive in the correct sequence | | ✓ | | data is transmitted in both directions, but only one direction at a time | | | ✓ |
2. 3(b) Any three from: - Can charge/power the mobile device (at the same time); - (Uses serial transmission so) data less likely to be skewed / corrupted; - Universal / industry standard / connection; - Cable can only be plugged in one way // Cannot be inserted incorrectly; - Fast transmission speed; - Backward compatible; - Supports different transmission speeds; - Automatically detects device // Automatically downloads drivers