| 摘要 |
<p>A communication system includes first and second communication units. The first communication unit (1, 2) sends transmission data, a control sequence, and an extended control sequence. The control sequence is originally defined by a protocol, and includes an abort sequence requesting for abortion of the transmission data. The extended control sequence (25, 26, 52, 53, 55, 57) is undefined by the protocol and is provided for requesting an extended operation. The second communication unit (4, 5) receives the transmission data, the control sequence, and the extended control sequence, and executes the extended operation in response to the extended control sequence. The extended control sequence includes the abort sequence.</p> |
