NI myRIO constant -3V on analog output

[Xenorollmops]

Hi Bob,

A nice idea you had there with the BoB. For quiet some time I do not use the break out board and connect direct to the pin of interest. Additionally I double checked the adjacent pins to rule out accidental pin mix-up. 

Once more, good intuition, but I already ruled that one out.

Is there a chance, that the MyRIO has a hardware fuse on the PCB for the MXP connectors AOs, which might be blown and is easily replaceable?!

Have a good one

Xeno

[Bob_Schor]

Xeno,

     I'm truly disappointed that my "brilliant idea" (where I made a stupid mistake connecting to the wrong pins and assumed you were just as careless as I) was the "wrong answer" and didn't fix your problem.

     So I'm left with the possible conclusion that maybe your myRIO really is "broken".  Is there any possibility that you can borrow another myRIO and try the same simple test?  I have no idea if there is a fuse on the AO lines inside the myRIO -- I'm not enough of a "hardware expert" to venture inside a myRIO.

     What I would do is to try to get in touch with the hardware support people at National Instruments, who might be able to advise you about trouble-shooting your myRIO.  

     Another idea just came to me.  If you cannot borrow another myRIO, can you "borrow" a skilled Electrical Engineer (I'm definitely not one of those) to consult with you and make a little plug-in circuit on one of the BreakOut boards to do a better test of the AI and AO capabilities of the MXP ports, something with reasonable loads and such additional test equipment as a small 5V power supply and a portable oscilloscope?  Sometimes having a second pair of hands and eyes on the problem can be helpful.

     I'm sorry I was unable to "solve" your problem.  Please feel free to send me a Private Message on this Forum to let me know if, and how, you resolve this.  I hope that the start of 2023 is more "positive" than the end of 2022 for you.

Bob Schor