Rcok 4 SE - two external disks not working?


I am having some issues with my rock 4 se, and I hope you can help me with this?
I want to run two external disks (Seagate Expansion Portable) both USB 3.0 enabled of my rock 4.

its like they cannot run both at the same time, any of you running two disk at once?

I can mount one of them, but if I then connect the other disk, the first disk starts to “click” and blink and both disks does not show up

I have tried all 4-USB ports on the rock without any luck

I just want to move some data from one disk to another :slight_smile:

Bonus info, the power supply i am using is this one
PD (Power Delivery)
Output USB A: 5V DC. 2,4A.
Output USB C: 5/9/12V DC. 3/2/1,5A.
USB-A: 2,4A/12 W
USB-C: 3,0A/18 W.
max. 30 W.

I think i found the answer by a little digging
FYI for all that find this post online:
If you want to use two hard drive, change to a 30W or more power adapter.

This might not work even with a bigger power adaptor:

See this: https://wiki.radxa.com/Rock4/FAQs

How much mA can i get from the USB 3 and 2 ports for charging or use a 2.5" disk?

The upper USB3.0 OTG has one dedicated current limit control which is 1.45A. The rest USB 3.0 HOST and the two USB 2.0 HOST share a current limit control of 3A together.

I xould not find the power consumption of the disks, but typically real hard drives take a lor, especially when power up.

Thank you for the update, I went out today to buy my a USB-C PD 65watt adapter to use… but its the same issue :frowning:

Do you have any idea what to do then?

and yes, its two 2.5" disks

If selling (and buying SSDs) is not an option, Not much. A SBC is just not built to power hungry USB devices. Even with a bigger power adapter, the current is limited.

You could put them behind a powered/active USB3 hub. Ensure that every port has the maximum current (some cheap models have the same “all ports can take 3A” rule) .This should work in general, but you might not been able to boot from them. Please note, that even some portable SSDs might draw to much power.

For Rock 4’s (except the crippled 4C+ V1.41) M.2 SSDs are best if you need a big disk. And one additional external disk attached to USB3 should probably work. Or use the Penta HAT (with external power). M.2 disks and the Penta HAT uses the PCI lane of the RK3399, this is faster and more reliable then USB3 disks.

Thanks, I will look into that.

would this work? or how is it with the "all ports can take 3A” rule :no_mouth:

Unfortunately I cannot answer this. To my knowledge, an USB-A pport must provide up to 0.9A, which is less the the 1.45 the OTG port promises, while an USB-C port provides up to 3A. Still, my portable CD-ROM works on my HUB, but NOT on the USB directly. So, best option would be to buy at a place were you can return it if it doesn’t work, sorry.

I think there is more to this thread than the “no, it can’t be done”. Beyond the power supply issues, I suspect there is some problem with the USB3 connection to the two drives.

I got the same two hard drives as @WebFinder_42 and I quickly noticed the same behavior that he describes. They seem to alternate activity.

I assumed that this was a power issue and got myself a powered USB hub that can deliver (hopefully) sufficient power to the disks. The disks are 2.5’’ which are reasonably low-pwered. When I plug the disks through the USB hub into a USB3 port on the Rock 4SE there are still problems. The write speed to both disks is really unstable and drops to almost zero for tens of seconds at a time. After a while the Rock 4SE will crash altogether and needs to be rebooted.

Interestingly, when I plug the USB hub through the USB2 port they seem to work reliably. The writing speed is constant and the Rock 4SE does not seem to crash.

It is possible that the USB2 requires less power from the ports, but that seems strange as the drives still require the same amount of power to run.

Wondering if anyone has any idea on how to further troubleshoot this problem.