Correct
The term heartbeat is just something I "made up" for EFILive. Basically all EFILive is trying to do is to find some "bus silence", i.e. when no other module is transmitting any data. It needs the silence so it can send the "stop chatter" command without the stop chatter command being garbled by some other module transmitting data on the bus while EFILive is halfway through transmitting the "stop chatter" command. So I figured the best way to "know" when there will be some bus silence is to record all the chatter and analyze the time between each frame of chatter data. The frame that has the most time between it and the next frame is what I call the "heartbeat" frame. You can choose any from you like but it has to be a frame in which the first "n" bytes are unique and do not change. The first "n" bytes are the bytes you enter for the "chatter" frame - that's what EFILive looks for on the bus. When EFILive sees that sequence of bytes it knows that it can transmit the "stop chatter" command once the current frame is complete.
Check those only if the ECM sends back a reply when EFILive transmits the stop/start chatter commands. You can verify that by turning on the menu option: View->Serial I/O. That will show the frames being sent/received.
Regards
Paul





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