LE-series records the time stamp every frame. However, in ASYNC communication, there are many types of frame end. LE-series ends the frame when it has more than 100ms Idle time in SD and RD. In another word, it will not record time frames when you monitor/simulate communication that does not have more than 100ms Idle time. If the frame ends with a specific word, register the word cord as a frame end. And then you will be able to record the time frames.

* You can set the frame end time a range of 1 to 100ms on Ver1.08 or later.(Adds "FRM TIME")