| 摘要 |
An apparatus for optimizing multiplexer communications in a system having a host, a multiplexer, and a field instrument device. The host is arranged to run a host software and to transmit a message to the multiplexer, the messag e including an embedded message for the instrument device. The host re-transmi ts the message until a response to the message is received from the device via the multiplexer, with the first re-transmission occurring after a long delay and a second and all subsequent re-transmissions occurring after a second ti me interval. An optimizing controller is arranged to establish a count indicati ng the number of re-transmissions occurring before the response has been communicated to the host, assess a message turnaround time based on the communication time it takes to transmit the message from the host to the multiplexer and to transmit the response from the multiplexer to the host, establish a bracket width at least as long as the message turnaround time, establish a short delay, and vary at least one of the long delay and the sho rt delay to minimize the count.
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