Got 2 brand new SPRacing F3 acro boards that I thought Id try out. I run Spektrum (and naze32's) up to this point. I configured the SP3 board for spektrum as required. 

1- wire to ground/signal of UART3. 
2. 3.3v from the 3.3v pad. 
3- Enable UART3 for Serial RX in the ports tab. 
4. Enable RX_serial under RX mode. 4-Enable Spektrum 2048. 
--SAVE--


I've got it working. But here's the issue. 

My SP3 board looses TX signal inputs and then the red light on the board starts flashing. Sometimes it comes back on, sometimes it doesn't. If I watch my receiver tab in CF, I can see it working (bar graphs moving) then it will loose signal and all the tabs go to 1500 straight down the board, like i turned off the TX. Then it will come back on.

I have 2 brand new boards, and they are both doing the same thing. Note, on my other quads running a spektrum sattelite and Naze32, NONE of them do this...
Have I got the sp3 board configured wrong ???

 
I don't have OSD on it so it shouldn't be a power issue i think (drawing too much current etc). the on rly thing connected to the board is the spektrum sattelite, the motors, and a beeper. Its not loosing power to the Sat, just signal. The light on the sat never goes off.

How close is your TX to the RX when this is happening? Try moving it at least 10 meters away and see if anything changes. Some RX doesn't like to get too close to the TX.

Also I think you need to check voltage. I've had a NAZE32 running on the bench and everything LOOKED just fine. Was running on 3.3 volts..

(06-Apr-2016, 02:37 AM)JoshSky Wrote: How close is your TX to the RX when this is happening? Try moving it at least 10 meters away and see if anything changes. Some RX doesn't like to get too close to the TX.

Also I think you need to check voltage. I've had a NAZE32 running on the bench and everything LOOKED just fine. Was running on 3.3 volts..

Checked voltage, it's running on solid 3.2V.

---

update:

After trying all different firmware versions, 3 different Spektrum DSMX sats, 2 different sat leads, and hours worth of troubleshooting I got it working.

Something is not working with the UART3 Rx header. I ended up using UART2 for Grd and Signal and remained with the 3.3v of its own pad. Works great. Test hovered complete.

It might be useful for people having same issue: I used pins 1&4 from Uart 2. I removed pins 2&3 from the socket. Pin 1 I attached to the ground wire to the sat. Pin 4 I used for the signal. I left the power wire to the 3.3v pad. Then in the clean flight... Go to the ports tab and switch off serialrx on Uart 3 and switch on serial rx on Uart 2. Done.

i had issues with uart3 having glitches while flying, moved the RX to uart2 and it works fine since then