Hello all
Following on from my previous post about this I thought I would have another try. If nobody is interested then so be it but I am a bit confused as to the power layout on the Pi 5 and the little bit of trouble I am having with a (yes, cheap) touch screen. I have one of these, which is pretty good given its price: https://www.amazon.co.uk/dp/B0CKSTLXBW? ... ct_details
The screen has 1920 resolution which is why I like it so much for my needs. However it is a bit power hungry and with usb_max_current_enable=1 set I can just about run it from the USB port on the pi with a USB c lead. This gives it both power and the touch input. However I think it is right at the limit of what the Pi's USB can deliver.
As I mentioned in my previous post. With its external 12v plug in power supply connected, the Pi's fan runs continuously when the Pi is shut down. Also, with the 12v psu powering the screen the Pi's USB ports don't work unless I am using a power supply that I bought for my Pi 4 or my USB C laptop supply.
I purchased a dual USB C lead (two male usb A connectors, one for data and one for power) to see if that helped but I get the same behavior. However if I connect it to the Pi USB via a passive USB hub the touch input (and the Pi's USB ports) work fine. This is with one USB A connector pulling power from my external 5 amp 9-36v buck power supply, and the USB A data connection connected via a usb hub.
dmesg -w gives me continuous:
USB disconnect, device number 30
[ 141.104557] usb 3-1: USB disconnect, device number 19
[ 141.268687] usb usb4-port1: over-current change #63
[ 141.268747] usb usb2-port1: over-current change #63
[ 141.420606] usb usb3-port2: over-current change #32
[ 141.556590] usb usb3-port1: over-current change #39
[ 141.800712] usb usb1-port1: over-current change #35
[ 141.936599] usb usb1-port2: over-current change #34
[ 141.964543] usb 3-1: new full-speed USB device number 20 using xhci-hcd
[ 142.113974] usb 3-1: New USB device found, idVendor=04f3, idProduct=5515, bcdDevice=57.11
[ 142.113980] usb 3-1: New USB device strings: Mfr=4, Product=14, SerialNumber=0
[ 142.113982] usb 3-1: Product: Touchscreen
[ 142.113984] usb 3-1: Manufacturer: ELAN
[ 142.134929] input: ELAN Touchscreen as /devices/platform/axi/1000120000.pcie/1f00300000.usb/xhci-hcd.1/usb3/3-1/3-1:1.0/0003:04F3:5515.001B/input/input66
[ 142.135020] input: ELAN Touchscreen UNKNOWN as /devices/platform/axi/1000120000.pcie/1f00300000.usb/xhci-hcd.1/usb3/3-1/3-1:1.0/0003:04F3:5515.001B/input/input67
[ 142.135064] input: ELAN Touchscreen UNKNOWN as /devices/platform/axi/1000120000.pcie/1f00300000.usb/xhci-hcd.1/usb3/3-1/3-1:1.0/0003:04F3:5515.001B/input/input68
[ 142.135236] hid-multitouch 0003:04F3:5515.001B: input,hiddev96,hidraw0: USB HID v1.10 Device [ELAN Touchscreen] on usb-xhci-hcd.1-1/input0
[ 142.140076] usb usb3-port1: over-current change #40
[ 142.168707] usb usb4-port1: over-current change #64
[ 142.168753] usb usb2-port1: over-current change #64
[ 142.276620] usb 3-1: USB disconnect, device number 20
[ 142.300665] usb usb1-port1: over-current change #36
[ 142.384735] usb usb2-port1: over-current change #65
[ 142.384788] usb usb4-port1: over-current change #65
[ 142.440696] usb usb1-port2: over-current change #35
[ 142.548683] usb usb3-port2: over-current change #33
[ 142.600627] usb usb4-port1: over-current change #66
[ 142.600662] usb usb2-port1: over-current change #66
[ 142.684636] usb usb3-port1: over-current change #41
[ 142.848572] usb 1-2: new high-speed USB device number 33 using xhci-hcd
[ 142.996795] usb 1-2: New USB device found, idVendor=1a40, idProduct=0101, bcdDevice= 1.00
[ 142.996800] usb 1-2: New USB device strings: Mfr=0, Product=1, SerialNumber=0
[ 142.996803] usb 1-2: Product: USB2.0 HUB
[ 143.028716] usb usb4-port1: over-current change #67
[ 143.028765] usb usb2-port1: over-current change #67
This stops when I connect it via a USB hub and the touch input (and a normal USB mouse) starts to work. This is for a 12v project so official mains PSUs aren't an option. The back feeding of the Pi via USB happens with the dual USB lead whether the touch screen is connected or not.
I'm interested in knowing why it is happening. Why the USB ports work with a laptop power supply/ Pi 4 power supply but not the buck converter, which claims to have a quick charge identification chip. And if there is a solution available. For instance, I wondered if doctoring the USB cable and removing the +5v wire feeding the Pi USB port might help but I would like some input before I start randomly trying things.
Any helpful thoughts?
Following on from my previous post about this I thought I would have another try. If nobody is interested then so be it but I am a bit confused as to the power layout on the Pi 5 and the little bit of trouble I am having with a (yes, cheap) touch screen. I have one of these, which is pretty good given its price: https://www.amazon.co.uk/dp/B0CKSTLXBW? ... ct_details
The screen has 1920 resolution which is why I like it so much for my needs. However it is a bit power hungry and with usb_max_current_enable=1 set I can just about run it from the USB port on the pi with a USB c lead. This gives it both power and the touch input. However I think it is right at the limit of what the Pi's USB can deliver.
As I mentioned in my previous post. With its external 12v plug in power supply connected, the Pi's fan runs continuously when the Pi is shut down. Also, with the 12v psu powering the screen the Pi's USB ports don't work unless I am using a power supply that I bought for my Pi 4 or my USB C laptop supply.
I purchased a dual USB C lead (two male usb A connectors, one for data and one for power) to see if that helped but I get the same behavior. However if I connect it to the Pi USB via a passive USB hub the touch input (and the Pi's USB ports) work fine. This is with one USB A connector pulling power from my external 5 amp 9-36v buck power supply, and the USB A data connection connected via a usb hub.
dmesg -w gives me continuous:
USB disconnect, device number 30
[ 141.104557] usb 3-1: USB disconnect, device number 19
[ 141.268687] usb usb4-port1: over-current change #63
[ 141.268747] usb usb2-port1: over-current change #63
[ 141.420606] usb usb3-port2: over-current change #32
[ 141.556590] usb usb3-port1: over-current change #39
[ 141.800712] usb usb1-port1: over-current change #35
[ 141.936599] usb usb1-port2: over-current change #34
[ 141.964543] usb 3-1: new full-speed USB device number 20 using xhci-hcd
[ 142.113974] usb 3-1: New USB device found, idVendor=04f3, idProduct=5515, bcdDevice=57.11
[ 142.113980] usb 3-1: New USB device strings: Mfr=4, Product=14, SerialNumber=0
[ 142.113982] usb 3-1: Product: Touchscreen
[ 142.113984] usb 3-1: Manufacturer: ELAN
[ 142.134929] input: ELAN Touchscreen as /devices/platform/axi/1000120000.pcie/1f00300000.usb/xhci-hcd.1/usb3/3-1/3-1:1.0/0003:04F3:5515.001B/input/input66
[ 142.135020] input: ELAN Touchscreen UNKNOWN as /devices/platform/axi/1000120000.pcie/1f00300000.usb/xhci-hcd.1/usb3/3-1/3-1:1.0/0003:04F3:5515.001B/input/input67
[ 142.135064] input: ELAN Touchscreen UNKNOWN as /devices/platform/axi/1000120000.pcie/1f00300000.usb/xhci-hcd.1/usb3/3-1/3-1:1.0/0003:04F3:5515.001B/input/input68
[ 142.135236] hid-multitouch 0003:04F3:5515.001B: input,hiddev96,hidraw0: USB HID v1.10 Device [ELAN Touchscreen] on usb-xhci-hcd.1-1/input0
[ 142.140076] usb usb3-port1: over-current change #40
[ 142.168707] usb usb4-port1: over-current change #64
[ 142.168753] usb usb2-port1: over-current change #64
[ 142.276620] usb 3-1: USB disconnect, device number 20
[ 142.300665] usb usb1-port1: over-current change #36
[ 142.384735] usb usb2-port1: over-current change #65
[ 142.384788] usb usb4-port1: over-current change #65
[ 142.440696] usb usb1-port2: over-current change #35
[ 142.548683] usb usb3-port2: over-current change #33
[ 142.600627] usb usb4-port1: over-current change #66
[ 142.600662] usb usb2-port1: over-current change #66
[ 142.684636] usb usb3-port1: over-current change #41
[ 142.848572] usb 1-2: new high-speed USB device number 33 using xhci-hcd
[ 142.996795] usb 1-2: New USB device found, idVendor=1a40, idProduct=0101, bcdDevice= 1.00
[ 142.996800] usb 1-2: New USB device strings: Mfr=0, Product=1, SerialNumber=0
[ 142.996803] usb 1-2: Product: USB2.0 HUB
[ 143.028716] usb usb4-port1: over-current change #67
[ 143.028765] usb usb2-port1: over-current change #67
This stops when I connect it via a USB hub and the touch input (and a normal USB mouse) starts to work. This is for a 12v project so official mains PSUs aren't an option. The back feeding of the Pi via USB happens with the dual USB lead whether the touch screen is connected or not.
I'm interested in knowing why it is happening. Why the USB ports work with a laptop power supply/ Pi 4 power supply but not the buck converter, which claims to have a quick charge identification chip. And if there is a solution available. For instance, I wondered if doctoring the USB cable and removing the +5v wire feeding the Pi USB port might help but I would like some input before I start randomly trying things.
Any helpful thoughts?
Statistics: Posted by jimseng — Sun Jan 28, 2024 5:26 pm