Verdin Plus on Dahlia board only boots with USB C debug cable installed

Hello,

We are running a Verdin Plus (Verdin iMX8M Plus Quad 4GB Wi-Fi V1.0B) on a Dahlia V1.0C carrier board. Is there a simple explanation for why our Verdin Plus requires power over the USB C debug port to remain on?

We have found that the Verdin will only boot when a computer is connected to the USB C debug port with external DC plug also connected. When the debug port is disconnected, the Verdin will also shut off with indicator LED 6 illuminated red, though Dahlia power remains on. Additionally, when a Verdin Mini is connected to the Dahlia, the board boots up fine, regardless of whether the debug port is plugged in.

Hi @tissue

Thanks for this report. I’ve verified the behavior on my end but don’t have an answer for you at the moment. I’m checking with internal hardware resources and will let you know what I find.

Drew

Hi @tissue

I confirmed with our team that they are investigating this still but we do not have any specific updates at the moment.

Drew

Hello,

for the Verdin imx8M Plus you should use at leat the Dahlia V1.1V
https://developer.toradex.com/verdin-sample-phase-over
the V1.0B was an early adapter sample board.

first I would try to remove the jumper JP7. this jumper disconnects the FTDI connection to the FORCE_OFF and the rest of the Power Control Debug Signals. There was a Problem with the FORCE_OFF when the FTDI chip was not programmed. Also we improved the the circuit quit a bit in the new Dahlia version.

You only mentioned the Debug USB-C. But just in case you mean the USB-C DRP there is also a SW Problem where the power can not be switch off when the USB-C DRP port is connected this is due some backfeeding.

Best Regards,

Matthias Gohlke