Top Board does not power on when using external PS

Good evening,

I can upload the test script for the D21G and it works while plugged in via the USB.

But when I apply external power it does not boot up the top board and LCD.

verified with multimeter, and also verified FUSE.

Any thoughts?

Josh Nijenhuis
Josh Nijenhuis
| 2 1 1
Asked on 1/9/19, 12:09 AM


Please check if your code is waiting for the Serial Monitor to connect. If it has a line " while (!SerialUSB) " the sketch will block there until you connect the USB and open the Serial Monitor.

Are you connecting 12/24V to V+/V-? Do you see 4 green LEDs light up inside the INDIO? 3 on the baseboard and 1 on the topboard.

| 1 1 3
Answered on 1/9/19, 1:02 AM

Thanks, I realized that V- symbol on the physical devices means GND, I was connected to EARTH. I thought V- was for negative voltage input for better opamp performance possibly. I guess when you assume; you make a fool out of yourself(me) Thanks for your help.

Josh Nijenhuis
on 1/10/19, 12:07 AM

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Asked: 1/9/19, 12:09 AM
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Last updated: 1/9/19, 1:02 AM