問82
頻出度★☆☆
USB に関する記述のうち, 適切なものはどれか。
平成29年度 秋期 ITパスポート試験 問82
テクノロジ系コンピュータ構成要素 › 入出力デバイス
This question's explanation and your answers so far.
解説
問 82
Incorrectア
The USB transfer rate is determined at connection time by automatically negotiating (auto-adjusting) the highest speed that both the PC and the peripheral device can support. It is not something the user sets by manually choosing a mode, so it is incorrect.
Incorrectイ
Power supply via the USB cable (bus power) is limited to devices with low power consumption. Devices with high power consumption, such as printers and external drives, use their own power source (self power), so saying that power is supplied “entirely” through the cable is incorrect.
- ウ
正解 The correct answer is ウ. For USB connectors on the peripheral-device side, in addition to Type-A and Type-B, several shapes are standardized, such as mini-B and micro-B for small devices and the vertically symmetric Type-C. Because they are used selectively according to the purpose and device size, the statement “there are several types of connector shapes on the peripheral device side” is correct.
Incorrectエ
USB stands for Universal Serial Bus and is a serial interface that sends data one bit at a time in sequence over a single (one pair of) signal line. Calling it a parallel interface that sends over multiple signal lines simultaneously is incorrect.
ここがポイント
- USB is a serial interface, and its transfer rate is determined by automatic negotiation at connection time (not manually set by the user).
- USB connectors come in several shapes such as Type-A/B, mini, micro, and Type-C; power supply comes in both bus power (via the cable) and self power (its own power source), so not all devices are cable-powered.
用語