I'm using an MSO9254A 'scope to monitor an RS422 serial line for a "heartbeat" message, that occurs at 100 ms intervals, interspersed with other traffic. The message is about 350 us (115.2 Kbps) and I'm triggering on the first 2 hex digits using the protocol trigger and serial decode. I've been able to save screen captures to an external USB memory as well as save up to 8192 triggers to segmented memory. The problem is that I suspect that there are heartbeat messages missing intermittently - say, one every few hours - so I'd like to save the trigger times to a file for post processing. The segmented memory provides a maximum of 8192 segments, or about 13 minutes worth of triggered data, which is not sufficient for a rare event. Having a timeout on the protocol trigger - i.e. trigger if no heartbeat message occurs within, say, 150 ms - would be ideal. Failing that, simply writing the trigger times to and external file would be most useful. Thanks in advance if there are any takers.