| 摘要 |
Disclosed is a decentralized data-processing star network with a contention system, having a plurality of terminal devices and a concentrator to interconnect the terminal devices via a transmission medium. Any of the terminal devices can start to transmit a packet immediately after a pause disposed to prohibit all transmissions, the pause occurring every time a packet has been transmitted. The concentrator has a start bit generation device for generating a start bit in accordance with the timing that the terminal devices should transmit their start bits and a relay device for ORing the generated start bit with each bit of a packet modulated as predetermined with a first frequency, converting it into a packet modulated as predetermined with a second frequency, and sending it out. Each of the terminal devices is assigned a unique code for contention control and has a monitor device for ORing bits of the code sent from the concentrator with corresponding bits of a code to be transmitted, and monitoring the accordance between bits of the OR and corresponding bits of the code to be transmitted in order to suspend the transmission if they do not accord. The bit configuration of the unique code is either all logical 0s, one logical 1 in the first bit, or more than one logical 1 continuously from the first bit. <IMAGE> |
