| 摘要 |
<p>The serial data port of a terminal device is normally connected to a peripheral device for data transfer. A telephone connection with a public switched telephone network (PSTN) is monitored to detect, however, if there is an incoming priority data message. If so, the terminal device is notified of the priority message and is allowed to terminate its current data transfer with the peripheral device. The terminal device is then connected to the PSTN to receive the priority message. At the conclusion of the priority message, the terminal device is reconnected to the peripheral device to complete the interrupted data transfer. In this way, the serial port of the terminal device can be used for data transfer with different peripherals, without jeopardizing or delaying reception of a priority data message.</p> |
