| 摘要 |
PURPOSE:To improve data transfer efficiency by stopping the polling operation for a no-answer terminal device which is a polling objective terminal device for a specific period. CONSTITUTION:A polling control table 7 contains a field 7a where the equipment identification number of a terminal to be polled for and a counter field 7b. Further, a polling stop frequency Q for omitting polling for a terminal device which makes no answer to a specific polling try for the specific period is set in the field 7b, and the set number is counted down every time a polling sequence is repeated. A retry frequency counter 8 displays the frequency of a retry of polling for the terminal device which makes no answer, and stops the retry when the frequency of the retry attains to a specific number R. |
