Great question! We need a dedicated tutorial for this, but in the meantime, check out the section about "Running with no USB output" of this tutorial: http://jevois.org/tutorials/UserPanTilt.html
In your case, try this (first just copy and paste the lines one by one to your serial terminal; once confirmed, you can also put them into the JEVOIS:/config/initscript.cfg file of your microSD). You should not have AMCAP running when you do this, just a serial terminal connected to JeVois:
setmapping2 YUYV 640 480 15.0 JeVois DarknetYOLO
setpar serout USB
setpar serstyle Detail
streamon
Use "setpar serout Hard" instead of USB to send the messages to the 4-pin hardware serial port. The serstyle Detail is to get the class names (see http://jevois.org/doc/UserSerialStyle.html)
Here is the output I get here after launching these commands and then leaving the camera on my desk and going to walk in front of it at some distance:
...
DKY 38
DKY 39
D2 person -466 -1466 484 -1466 484 -172 484 -1466 28.0
DKY 40
D2 person -490 -1538 502 -1538 502 -150 502 -1538 37.8
DKY 41
D2 person -373 -1534 511 -1534 511 -172 511 -1534 43.3
DKY 42
DKY 43
D2 person -616 -1236 472 -1236 472 18 472 -1236 25.7
DKY 44
...