On Mon, Dec 18, 2023 at 12:56:55AM +0100, Arnt Karlsen wrote:
> On Sun, 17 Dec 2023 12:50:57 +0000, ael wrote in message
> <ZX7usUPDkXqZiK0b@???>:
>
> > On Sun, Dec 17, 2023 at 11:47:02AM +0100, Arnt Karlsen wrote:
> > > On Sat, 16 Dec 2023 17:02:20 +0000, ael wrote in message
> > > <ZX3YHIly7x-Dhh2R@???>:
> > >
> > > > I have recently received a Raspberry Pi 5, although I am still
> > > > awaiting a power supply so I can't try it yet.
> > >
> > > ..if you have any 5V supply, e.g. an usb cellphone charger,
> > > a BEC or an ESC for electric RC model motor throttle control
> > > meant to power the RC receiver and a few servos, will work.
> >
> > Actually the PI 5 uses USB-C with PD implemented, so it really
> > needs a proper USB-C supply with full PD support.
> >
> > I am not sure how many of those supplies that you mention
> > are USB-C compliant.
>
> ..my RC model power tricks are not USB-C compliant AFAIK,
> they are workarounds, bypassing all the fancy new USB-C
> compliant stuff, so verify your voltages, and, chk out:
> https://www.raspberrypi.com/documentation/computers/raspberry-pi-5.html
Ah, yes. I had forgotten that RP wasn't really following the PD spec
and instead keeping to 5V with increased current.


> > > Pi's, so verify your voltage.
> >
> > I have an original RP and also an RP3 and I don't have
> > problems with them. As I recall without checking the
> > RP5 has extended that tolerance to at least 5V5 and maybe more.
>
> ..nice, might tolerate my 5.1V chain saw magneto spool then.
> 70 turns around the iron core, a rectifier bridge, and one
> capacitor on each side of the 7805, and a 0.1V zener diode
> to hike the 7805 output to 5.1V, neatly epoxied into a wee
> metal box bolted onto the engine, so no idea what capacity
> those 2 capacitors were, or, are now, worked fine powering
> 7 servos and the receiver silky smoothly in my 42 year old
> noisy ass gas plane.

I do have a couple of little adapter cards which attach to a standard ATA PSU,
and so can provide large currents at 3v3, 5V and more. I have many
old/spare ATA PSUs lying around, so they provide very economical
solutions of, I think high quality and protected, power. Yet to try
them, but I did get them for powering a possible farm of RPis or even
Orange PIs. When I have a bit more time...

> > I think that it uses the USB-C PD at 9V in some (all?)
> > circumstances, so presumably it can tolerate at least that
> > potential on the USB-C connector.

As I said above, I got that wrong. The RP5 wants 5V @ 5A rather than 9V
from PD.

> ..I wouldn't be too sure we have all the drivers for the new
> stuff in the rpi5, but we are able to use their rpi-specific
> drivers from their site.
>

I suppose that I should also be worrying about the compiler flags set
for all the packages to take full advantage of the Cortex-A76
instruction set.

But it is very early days and I won't have time to try anything for a
week or two at best.

Again, thanks for the reply and information.

ael