<![CDATA[Serial Monitor: Reversed question marks when on battery]]>Hi,

I am creating my first sensor using a easypcb. It has two reed switches, one on D3 and the other on D8 (via an IRS).

When I power the sensor from an USB port the output in the serial monitor looks fine, but when I power it via battery (2 AA rechargables, 2.6v in total) the output contains reversed question marks:

12:45:04.443 ->  __  __       ____
12:45:04.443 -> |  \/  |_   _/ ___|  ___ _ __  ___  ___  _ __ ___
12:45:04.443 -> | |\/| | | | \__⸮ \ / _ \ `_ \/ __|/ _ \| `__/ __|
12:45:04.443 -> | |  | | |_| |___| |  __/ | | \__ \  _  | |  \__ \
12:45:04.443 -> |_|  |_|\__, |____/ \___|_| |_|___/\___/|_|  |___/
12:45:04.476 ->         |___/                      2.3.2
12:45:04.476 -> 
12:45:04.476 -> 16 MCO:BGN:INIT NODE,CP=RPNNA---,FQ=8,RE⸮=255,VER=2.3.2
12:45:04.476 -> 28 T⸮M:INIT
12:45:04.476 -> 28 TSF:WUR:MS=0
12:45:04.476 -> 32 TSM:INIT:TSP OK
12:45:04.476 -> 34 TS⸮:INI⸮:ST⸮TID=1
12:45:04.476 -> 36 TSF:SID:OK,ID=1
12:45:04.476 -> 38 TSM:FPAR
12:45:04.476 -> 43 ?TSF:MSG:SEND,1-1-255-255,s=255,⸮=3,t=7,pt=0,l=0,⸮g=0,⸮t=0,st=OK:
12:45:06.499 -> 2052 !TSM:FPAR:NO REPLY

This has been soldered to the PCB:

  • Arduino Pro Mini 3v
    RFM69HW
    Antenna
    //Battery Measurement
    1M Ohm
    470k Ohm
    1uF Capacitor
    //Booster
    Step up Booster(to 3v)
    1uF Capacitor

Does that mean the booster is broken? Or did I use the wrong capacitor size? The easypcb says 0.1uF but I only had 1uF capacitors and I hoped it would work.

]]>https://forum.mysensors.org/topic/10881/serial-monitor-reversed-question-marks-when-on-batteryRSS for NodeWed, 22 Jul 2026 02:20:49 GMTSun, 12 Jan 2020 11:51:39 GMT60<![CDATA[Reply to Serial Monitor: Reversed question marks when on battery on Mon, 13 Jan 2020 17:00:20 GMT]]>@kiesel said in Serial Monitor: Reversed question marks when on battery:

@Yveaux thanks, what could be the reason for them?

Baud rate could be slightly off, or crappy connections,or ....

And by xomms you mean Serial, not the rfm69, right?

Correct

]]>https://forum.mysensors.org/post/103215https://forum.mysensors.org/post/103215Mon, 13 Jan 2020 17:00:20 GMT<![CDATA[Reply to Serial Monitor: Reversed question marks when on battery on Sun, 12 Jan 2020 20:40:51 GMT]]>@Yveaux thanks, what could be the reason for them? And by xomms you mean Serial, not the rfm69, right?

]]>https://forum.mysensors.org/post/103203https://forum.mysensors.org/post/103203Sun, 12 Jan 2020 20:40:51 GMT<![CDATA[Reply to Serial Monitor: Reversed question marks when on battery on Sun, 12 Jan 2020 16:27:34 GMT]]>@kiesel said in Serial Monitor: Reversed question marks when on battery:

/edit: There are less reversed question marks now, but there are still some.

There should be no illegal characters at all. Looks like there's still a comm issue.

]]>https://forum.mysensors.org/post/103199https://forum.mysensors.org/post/103199Sun, 12 Jan 2020 16:27:34 GMT<![CDATA[Reply to Serial Monitor: Reversed question marks when on battery on Sun, 12 Jan 2020 12:38:04 GMT]]>Well, it seems the problem might have been that the booster capacitor was touching the booster.

Only problem left is a lot of NACKs, but I will create a different topic for that.

/edit: There are less reversed question marks now, but there are still some.

]]>https://forum.mysensors.org/post/103187https://forum.mysensors.org/post/103187Sun, 12 Jan 2020 12:38:04 GMT