USB boot power drop

A query based on total ignorance.

I’ve been using a USB powered TP-Link router as a wireless bridge for my Risc PC but these days it’s rarely switched on. Retained for love.

I’d like to move the router to either my BB -xM or RPi 4. Problem is, it only works if the router is powered other than from the connected machine because the USB ports lose power during start-up/re-boot so negotiation doesn’t succeed.

Is the loss of power unavoidable or would it be possible to change that in a future OS release?

@ Frederick

Is the loss of power unavoidable or would it be possible to change that in a future OS release?

I am not sure I understand your question correctly, so apologies in advance if my answer may result off-topic.

When RISC OS boots, and until the Desktop is initialised, it tends to spin the CPU up, so yes RISC OS boot, and also when you press F12 and temporarily exit the desktop, are higher power consumption situations.

It can be solved, but, AFAIK, it has not been addressed yet. Rick M. had a good proposal to fix it, at least for when the OS is in CLI mode (not sure if it would also work when the system is at boot time).

However, having a PSU that can deliver enough power, should help in your case? Is using a separate PSU a problem in your case?

If the issue is to have a single power-on button, would an external USB HUB (powering both your board and the router) help?

If it’s anything like the Tenda W150M portable wireless AP/router I have, it takes a minute to sort itself out before being usable. And needs more power than the RPi can supply. Rating plate is 5V 1.2A.

I am not sure I understand your question correctly, so apologies in advance if my answer may result off-topic.

I think the problem Fredrick is seeing is that when he reboots the BB-xM or Pi, the 5V line on their USB ports drops out temporarily, meaning anything powered from the USB sockets (such as his router) ends up rebooting.

@ Andrew

I think the problem Fredrick is seeing is that when he reboots the BB-xM or Pi, the 5V line on their USB ports drops out temporarily, meaning anything powered from the USB sockets (such as his router) ends up rebooting.

Haaa thanks Andrew! Then, the external USB HUB that powers both the board and the router and use an on/off switches should be a possible solution. Using the same powered HUB, should allow the board to see the USB device and, when the board reboots, the device stays powered up.

I think the problem Fredrick is seeing is that when he reboots the BB-xM or Pi, the 5V line on their USB ports drops out temporarily

Yup, that’s it.

the external USB HUB that powers both the board and the router and use an on/off switches should be a possible solution

The BB is powered by a meaty power supply and I’d rather keep it that way. I powered the router from the hub attached to my Mac to test the bridge & that was fine. I was just thinking that it would be nice to have things self contained.

After getting a connection I can transfer the USB plug to the BB -xM and then it ‘just works’.