| 摘要 |
<p>In a camera system, which shares an isochronous band to transmit image signals captured by a plurality of cameras (5A, 5B) to a host PC (1) in real time in image frame units via an IEEE 1394 bus (3), the cameras (5a, 5b) are equipped with an asynchronous streaming packet receiving circuit (52), which receives asynchronous streaming packets transmitted to the IEEE 1394 bus (3), an asynchronous streaming packet transmitting circuit (53), which transmits asynchronous streaming packets to the IEEE 1394 bus (3), and an image output switch (54), which is controlled by the asynchronous streaming packet receiving circuit (52) and transmits image data output from the image pickup unit of the camera to the IEEE 1394 bus (3) by means of isochronous packets. When the asynchronous streaming packet receiving circuit (52) receives an asynchronous streaming packet addressed to it conveying use rights for an isochronous band, an acknowledge packet is transmitted from the asynchronous streaming packet transmitting circuit (53) and the image output switch (54) is set to an on state in which isochronous packet transmission is enabled.</p> |
