Gettin started with a Pi

OK, so I’ve finally tried out my new RPi (thanks David!).

I connected it up and got a picture on the screen. All seemed well, and I started to play. I got as far as trying to setup the internet when the screen when blank and I lost the signal to the monitor. I switched on and off again, and now only get a few seconds of operation before it shuts down again. Sometimes I get to the desktop, sometimes not, but never for enough time to try to fix things.

I’m using a model B with RISC OS, plus a VGA adaptor for the monitor from CJE Micros. Power supply is 5V. After losing the picture the power light on the Pi stays on red, but the SD card light stops flashing, so I’m not sure whether I’m just losing the connection to the monitor or if things have shut down entirely. On my first session I did start fiddling to get DCHP working, and have tried booting up with the ethernet cable both plugged and unplugged. Otherwise I didn’t get far enough to change any systems settings, etc

I’m guessing that it’s either a power supply issue or something to do with the VGA adaptor. Any ideas/suggestions for solving it?

If it is an original Pi, and you are handy with a soldering iron, you might want to consider modifying the HDMI to run off its own power.
https://www.heyrick.co.uk/blog/index.php?diary=20130729

Your description also suggests your PSU isn’t providing enough power (or your cable is dropping too much current).

I’m guessing that it’s either a power supply issue

Probably a good guess.

On Pi 1, it’s almost impossible to power more than a mouse without a powered hub.
Some keyboards are OK, but not mine, that draws to much power.

D-Link DUB-H4 is a very good hub. I use it for the Pi itself (so no need for the 5V power supply), my hungry keyboard, a mouse and some USB keys.

OK, that’s useful. I’ll get a powered hub, and see how I get on :)

My hub is off the internet – Duronic Aquadam 10 port powered hub, which, apparently rather naughtily, back-powers the RPi itself!

This is evidently not what the USB spec says, but it works for me!

I also have a TP-link hub in another country (d’occasion) which doesn’t do this back-powering, so need a separate PSU or a cheat lead to do the powering from the hub (USB ’phone charger lead!).

Both work.

On Pi 1, it’s almost impossible to power more than a mouse without a powered hub. Some keyboards are OK, but not mine, that draws to much power.

Are you sure it is a power issue? Never had a problem using any USB devices on Pi1. Is this a known issue?

I also have to question the “can’t power more than a mouse” statement; I have a Pi 1 (B+, I think; the one with micro SD) and can use a mouse, keyboard, flash drive and 2.5" hard drive all at the same time without external power.

(B+, I think; the one with micro SD)

Completely different beast.
First Pi don’t even boot with my hungry keyboard (a wired one).

There’s two issues with all Pi’s: The quality of the official PSU’s and Vdroop.

A few years back, I did a lot of testing for the Pi engineers to help track down USB issues, it became apparent that some of the official Pi PSU’s cannot supply the stated current and that using the USB ports in conjunction with the network card, without a powered hub could cause the CPU voltage to drop below Vmin.

You can also occasionally see data corruption whilst writing to a USB memory card, if Vdroop occurs during the write.

If you measure the voltage across the test points whilst altering the CPU loading, then hit the USB port with data, the Vdroop is pretty bad due to a lack of a VRM.

For the most part, the problem goes completely unnoticed. If you’ve ever had a key miss or stick, or the keyboard/mouse stop working all together, it’s more than likely due to Vdroop. If the Vdroop is sustained, you’ll get an indicator appear at the top right of the screen.

I certainly wouldn’t advice using any Pi without a powered hub, just to be on the safe side.

I have had a number of original Pi1 B which had faulty polyfuses which I have had to replace.

So I can confirm that the original Pis certainly had issues.

Well, no joy I’m afraid. Picked up a DUB-H4 hub as suggested. Plugged that in at the mains, the keyboard and mouse to the hub, and the hub to one of the Pi’s USB ports. Exactly the same behaviour – boots up, works for a while, then the screen goes black and the the Pi’s red power light is the only one left on.

Should I be connecting the USB hub to the Pi’s power socket? In which case I’ll need to buy a USB – micro-USB cable. If not, then I wonder if it is some issue with the VGA adaptor?

I had somewhat similar problems 3-4 months ago. Turned out to be the USB keyboard. Does it continue working if there is no keyboard?

Does it continue working if there is no keyboard?

Thanks for the suggestion, but seems to make no difference.

In case it’s relevant, the time to blackout shrinks the more I try to use the Pi. From the first attempt made after the Pi’s been idle for a while, I can get to the desktop and use it for a minute or so. Subsequent attempts each result in a shorter window before it blacks out, until I can no longer complete the boot sequence at all.

You could try fiddling with the config_hdmi_boost setting in config.txt. It’s possible the default setting is only just enough to power the VGA adapter, and then as the board warms up the power output/requirements shift a bit and it dies.

https://www.raspberrypi.org/documentation/configuration/config-txt.md

(Note that although that page describes the default setting as being zero, I’m fairly certain they increased it, either in later firmware versions or for later Pi models)

In case it’s relevant, the time to blackout shrinks the more I try to use the Pi. From the first attempt made after the Pi’s been idle for a while, I can get to the desktop and use it for a minute or so. Subsequent attempts each result in a shorter window before it blacks out, until I can no longer complete the boot sequence at all.

Sounds like overclocking and/or overheating issues. Do you have an arm_freq, core_freq, sdram_freq or any over_voltage settings in CONFIG.TXT? Try forcing, or underclocking it. For Pi1 the defaults are arm_freq=700 and core_freq=250.

If not, then I wonder if it is some issue with the VGA adaptor?

There is only one way to know… test it with an HDMI screen.

Thanks Jeffrey/John. No joy either – same symptoms. My current config.txt is:

fake_vsync_isr=1
framebuffer_swap=0
gpu_mem=64
init_emmc_clock=100000000
config_hdmi_boost=7
arm_freq=700
core_freq=250
kernel=RISCOS.IMG

David – I’ll see if I can get it working on the TV.

Thanks to all. Still no luck, unfortunately. Tried all sorts of tweaks to the config.txt file, but still get the first blank after about 2mins of operation. I tried to connect to our HDMI TV, but this didn’t result in a picture. The TV seems to recognise the Pi, as the screen comes up with the message ‘Recorder 1(raspberry )’, but there’s no image.

I wonder if it’s a defective Pi?

I wonder if it’s a defective Pi?

Possible.
I’ll try to fix that…
Check your mailbox :)

I had one USB Cable that was not good enough for the RPi 1, got that replaced long ago. The RPi 1 does take more power than a lot of lower end power supplies put out (USB 2 only requires 0.5 amps per port, most provide 1.0 amps, the RPi 1 requires at least 1.5 amps, 2 amps recommended).

Well, thanks to David’s generosity, I have another Pi to play with. This one seems to be working fine, so I think that it must have been an issue with the first one somewhere. I’m using both the powered hub for the keyboard/mouse and the bundled power supply for the Pi itself – the hub alone doesn’t seem to have enough juice to keep the lights on, perhaps because of the VGA adaptor? Anyway, all good now, and looking forward to getting everything set up.

This does mean I have a non-functional Pi spare. I don’t really have any use for this, and David doesn’t want to have it back. Would it be of any use to a more knowledgeable person, who could perhaps coax it into working or use for spares? Free to a good home :)

Greetings. (or should that be !Greetings ?)

I followed the excellent instructions by David Pitt and got RiscOS working on a Rpi3. However, being a complete noob to RiscOS I do have some questions.

1. How do I get a command line? There does not seem to be anything on the Taskbar(?) to do this. I am able to center click on the raspberry, or CTRL+F12, and use the task window for commands.

2. How do I install NetSurf, and then activate it? It is still on the SD as a zip file.

3. When I left click on the USB-SCSI disk a warning pops up saying that ‘No boot code has been run at startup -bla bla…’

That’s enough for now.

Thanks in advance.

Len

When I left click on the USB-SCSI disk a warning pops up saying that ‘No boot code has been run at startup -bla bla…’

Is !Boot in the root of the SCSI device?

If the SCSI device is a disc the SCSIFSDrive should be set to 4.

How do I install NetSurf, and then activate it? It is still on the SD as a zip file.

Once the machine has properly booted the NetSurf zip can be opened with !SparkFS in the Utilities directory.

!Boot folder is on the root of the USB stick and that sticks window shows as SCSI::HardDisc0.$.

!Boot folder is on the root of the USB stick and that sticks window shows as SCSI::HardDisc0.$.

This is good.

What do the three *status commands report? (st. is an abbreviation for status.) The results from my Pi are:-

*st. FileSystem
FileSystem SCSI
*st. SCSIFSDrive
SCSIFSDrive 0
st. boot
Boot
*

I have added a note on what to do with NetSurf.