Rock p4 and Suptronics X400 power via GPIO


#1

I want use a x400 suptronics Soundcard on the Rock Pi 4. The x400 powers the CPU via GPIO Pin 2,4 with
5V/3A. Are there already experiences with this setup?
How much is the max power cunsum from the Board without USB Powered Devices?


#2

Have you seen the other specialties on the expansion board? I didn’t know the board, but I read the description briefly. It uses 6 more GPIO pins, for IR remote, I2S for digital sound and I2C for control.

GPIO2 (I2C1_SDA) Pin 3
GPIO3 (I2C1_SCL) Pin 5
GPIO18 (I2S_BCLK) Pin 12
GPIO19 (I2S_LRCK) Pin 35
GPIO21 (I2S_DOUT) Pin 40
GPIO17 (IR) Pin 11

Please have a look at the GPIO connector of the RockPi, the GPIOs are numbered differently and the I2C bus also has a different number. You should contact the manufacturer of the sound board to find out if these adjustments can be made in a config file, or if the software needs to be recompiled.

https://wiki.radxa.com/Rockpi4/hardware/rockpi4


#3

the x400 works with the Rpi3, the Pin umber for I2C1_SDA is 3 and not 2, yes is it a chaos.
pin 2 are confused wir GPIO2.
Before I connect the X400 I would check the really used pins in the Rpi drivers.


#4

Oh, sorry, I’ve corrected.


#5

Wow! Nice board! Didn’t even know it! Must get this! It’s so terrible to power SBC’s over micro USB, this is a great solution both for power and for audio :slight_smile:

I haven’t checked in the last 2 months, but the RockPi4 Linux kernel needs to support dt overlays. I don’t know if it does already? @Jack ?


#6

Overylay support is added now, but currently it’s limited to only one dtbo inserting into the dtb. We still have issue with multiple dtbo merge into the dtb.


#7

Sorry if I ask, but something is unclear to me. Is it limited to inserting an entry at a time, or can generally only one entry be inserted. Or in other words, is it possible to make a change in the dtb, reboot and then make another change?


#8

It means currently we can only enable only one dtbo, in this dtbo you can enabled multiple devices/nodes. But inserting multiple dtbo is not working yet.