Click for under power

Hello everybody.
My problem is that while I play I hear clicks simultaneously with the appearance of the under power icon on the display …
I tried with original raspberry 3A power supply and now I have mounted a stepdown with 12V 5A power supply. The problem remains.
On the board I mounted a Pimoroni fan (but the problem appeared even before), a usb audio dongle and the Adafruit 2.8 display.
I am powering from the 5V and GND pins of the GPIO.
Some advice?
Thank you

Did you use it through the USB C or through the RBPI4 GPIO header (<=> did you cut the power brick cable ?).

With USB C and RBPi official power brick You should not experience these troubles regarding your configuration.

Perhaps some USB device connected to the zynthian is draining too much power. Could you describe your hw setup?

It can be an absorption … On the raspberry I connected:
the Pimoroni fan.
A usb sound card dongle (I also connected a Focusrite and M-Audio sound card and the result doesn’t change).
The USB cable of a master-keyboard that has only three LEDs and has no display or other.
The Adafruit 2.8 display.

For le51,
I connected the two wires of the 12V power supply with stepdown adjusted to 5.2V directly on pins 5V and GND (pins 4 and 6) of the GPIO. What should I cut? Probably to prevent strain on the usb cable I assume.
Thank you

See if it does the underpower warning without anything usb plugged in to it.

Thanks baggy pants …
So, give further proof … with the Focusrite Scarlett 2i4 sound card which does not have its own power supply but only usb, the problem is solved … so it was probably the Chinese dongle … I could use a Sound Blaster SBX Pro … but Zynthian doesn’t see it (while alsamixer does).
I would like to know if to have MIDI in order to connect the Zynthian to a DAW (MixBus on Mac) I have to connect with a USB cable from the Raspberry port where it is powered (should I eliminate the power cable?) Or if I have to use a USBA / USBA … Sorry but I know very little about MIDI … usually I only work with audio tracks … Thanks for any info

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Also check your connections to the header. You need good quality, low impedance (relatively thick) wire that is well crimped. Many jumper wires are very thin and poorly crimped leading to poor conductivity between the pin and the connected device (PSU). I have found it difficult to get a good quality supply feed to the header pins.

It sounds like the PSU for the soundcard was causing current to flow from the RPi. Possibly a poor PSU causing oscillation / ripple / noise on the supply or ground loops. It is good that you have solved the power issue.

To connect Zynthian to a DAW you may wish to use its OTG/Gadget mode. This requires connecting its USB-C (power inlet) connector to the DAW’s USB and enabling OTG in webconf HARDWARE->Options. This presents Zynthian as a USB MIDI device to the host computer.

Another way would be to use a MIDI over network protocol such as RTP-MIDI (AppleMIDI network) or QmidiNet (IP Multicast) which may be enabled in webconf INTERFACE->MIDI Options or Zynthian admin menu.

Thanks (again) Riban,
I immediately thought of this too. But it also did it with the original 3A power supply. I think the problem was the Chinese dongle. With Focusrite it doesn’t happen anymore.
Also understood perfectly for the MIDI connection. You are very kind and very clear … thank you. So USB C cable on its socket without eliminating the cable that carries voltage to the USB port?

Yes, you must use Y cable, more details are in OTG Connection of Zynthian

Sorry Riban … but on Web conf on Hardware I find only KIT, AUDIO, Display and Wiring … where can I find Option ???
Thank you again

For ToFF:
I have no power problems … I connected a power supply to the GPIO pins, so I have the USB port of the Raspberry free.

This is maybe best way for OTG connection, thanks for clarification. I wish you a quick solution to your issue.

Thanks to you!

6 posts were split to a new topic: Raspberry Pi GPI pins and encoders