0

Raspberry PI AMP+ wont Boot

Mike Linnen

May 27, 2016 02:30

None

Follow

 I have a 12 volt supply that does 2.5 amps.  When I plug in the supply the Pi never seems to try and boot (no text is shown on a connected HDMI monitor in fact the monitor claims there is no input signal).  If I disconnect the 12 volt supply and power up the PI by the Micro USB the Pi will boot all the way to the bash prompt.

I suspected the power supply was the problem but I have tried 5 different power supplies and all behave the same way.

Any ideas on how I should trouble shoot the boot problem?

 

Thanks

Mike

• Facebook
• Twitter
• LinkedIn

4 comments

• 0
  
  HiFiBerry team May 27, 2016 07:01

  Hi Mike,

  if you are sure your power supply work and the polarity is right, this should work. When you boot with the USB power supply, can you load the Amp driver and it is listed by aplay -l?

  Best regards, Daniel 

• 0
  
  Mike Linnen May 28, 2016 12:50

  Yes the aplay -l returns the following:

  **** List of PLAYBACK Hardware Devices ****
  card 0: sndrpihifiberry [snd_rpi_hifiberry_amp], device 0: HifiBerry AMP HiFi tas5713-hifi-0 []
  Subdevices: 0/1
  Subdevice #0: subdevice #0

• 0
  
  Mike Linnen May 28, 2016 13:43

  A couple more details on what is happening.  I am using a Raspberry Pi 2 with a Raspberry Pi WiFi USB dongle.  I do not have any speakers hooked up at this time.

  When I power it up with a good 12 volt supply the following occurs:

  1. RED LED on Pi goes on steady - this tells me the 5 volts on the Pi is good
  2. The HDMI Display shows the color splash screen for a few seconds
  3. The HDMI Display goes blank and then the HDMI monitor shows a message "No Signal"
  4. The GREEN LED on the Pi never seems to come on or blink
  5. The boot sequence text never shows on the HDMI display and I cannot SSH into the device or ping it's IP.
  6. The 5V on the Pi is reading 6.5 volts.  There is a steady 12.5 V on the Amp+ on the screw terminals with the right polarity.

   

  When I disconnect the 12 volt supply and connect a USB supply to the Pi the following happens:

  1. RED LED on Pi goes on steady - this tells me the 5 volts on the Pi is good
  2. The HDMI Display shows the color splash screen for a few seconds
  3. The HDMI Display starts showing the boot sequence text
  4. The GREEN LED on the Pi flashes
  5. The 5V on the Pi is reading 5.05 volts.
  6. I can SSH into the Pi after the boot sequence completes.

   

  Note:  This setup with 12v external supply powering the Amp+ was working at one time for several days and I was getting sound out of the Amp+.  I have also swapped out the Raspberry Pi using the same WiFi adapter, Amp+ and SD card and it also does not boot (only thing different is the Pi itself).

  So it appears the Amp+ is not regulating down to 5V correctly and I think that is why the Pi is not booting.

  Edited by Mike Linnen May 28, 2016 16:01
• 0
  
  HiFiBerry team May 29, 2016 14:34

  Hi Mike,

  this is very strange as an over-voltage should damage the Raspberry Pi, which is not the case here. We need to test the Amp+ here. I will create a ticket for this and inform you about the next steps.

  Best regards,
  Daniel