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Something like a KVM switch for multiple Raspberry Pis
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James Harris
Sep 6, 2015, 1:00:51 PM9/6/15
to
I fancy setting up a few Raspberry Pis with different configurations.
Their small size would make them ideal for having many of them in a
reasonably small space and I would need them all to be viewable on a
single monitor (by switching).
One monitor, keyboard and mouse would probably do for them all. Anyone
aware of a good-value KVM solution for this? An 8-way would be enough.
Some sort of power distribution would be a bonus. Second hand would be
OK. Cheap components would be a double bonus.
I am not thinking of compute modules as the individual Pis could me
moved later.
Any of you guys already done this?
James
Their small size would make them ideal for having many of them in a
reasonably small space and I would need them all to be viewable on a
single monitor (by switching).
One monitor, keyboard and mouse would probably do for them all. Anyone
aware of a good-value KVM solution for this? An 8-way would be enough.
Some sort of power distribution would be a bonus. Second hand would be
OK. Cheap components would be a double bonus.
I am not thinking of compute modules as the individual Pis could me
moved later.
Any of you guys already done this?
James
Dave Higton
Sep 6, 2015, 4:46:08 PM9/6/15
to
In message <mshrck$o68$1...@dont-email.me>
Curiously, there seem to be no HDMI + USB KVM switches at anything
like sensible prices. There are some HDMI switches cheap, and there
are some USB switches cheap, but not integrated.
According to my last search of eBay and the WWW, anyway.
Dave
like sensible prices. There are some HDMI switches cheap, and there
are some USB switches cheap, but not integrated.
According to my last search of eBay and the WWW, anyway.
Dave
ray carter
Sep 6, 2015, 8:36:05 PM9/6/15
to
full machine and use ssh -X to login to the others remotely from that
machine. You could also set them up with xdmcp or use vnc (that would be
my last choice).
davehi...@gmail.com
Sep 7, 2015, 6:54:51 AM9/7/15
to
them to control the rest. Much cheaper, requires no extra hardware.
Dave
Gordon Levi
Sep 7, 2015, 10:54:33 AM9/7/15
to
"sudo apt-get install xrdp"
on each Pi makes them standard Windows remote desktop clients
<http://www.xrdp.org/>. Now you can use a single Windows (or Linux)
computer to display the same X Window desktop as that on your Pi.
Windows remote desktop makes it easy to automatically log into, and
switch between, Pis. It works well and I have never had any need to
connect a display, keyboard or mouse directly to a Pi.
I should add that I have not tried audio let alone some other devices
that you may be able to connect with a sophisticated KVM switch. To
counter that possible disadvantage you can use the power of your
Windows box for remote development in Python using Visual Studio
<http://microsoft.github.io/PTVS/> or Java using Netbeans.
James Harris
Sep 7, 2015, 12:42:29 PM9/7/15
to
"Dave Higton" <da...@davehigton.me.uk> wrote in message
news:9a460aff5...@my.inbox.com...
USB switch and individual switches. The integrated switches are much too
expensive.
Options? Perhaps these:
1. Convert USBs to PS/2s
2. Convert HDMIs to VGAs
3. Have one switch for USB and one for HDMI.
4. Use the network, as others have suggested.
5. Use the olde way and swap cables. :-(
I might have one or two machines in there for which the network would
not do as I would need to see them boot up, but it would do in some
cases. I could maybe have a hybrid solution mixing different solutions.
Sounds a bit complicated and it would not be as convenient as I wanted
but may be a practical way forward.
Thanks to everyone for the responses.
James
Andrew Smallshaw
Sep 13, 2015, 8:47:02 AM9/13/15
to
On 2015-09-06, James Harris <james.h...@gmail.com> wrote:
> I fancy setting up a few Raspberry Pis with different configurations.
> Their small size would make them ideal for having many of them in a
> reasonably small space and I would need them all to be viewable on a
> single monitor (by switching).
>
> One monitor, keyboard and mouse would probably do for them all. Anyone
> aware of a good-value KVM solution for this? An 8-way would be enough.
> Some sort of power distribution would be a bonus. Second hand would be
> OK. Cheap components would be a double bonus.
I'm a bit late into this discussion but as others have already said
> I fancy setting up a few Raspberry Pis with different configurations.
> Their small size would make them ideal for having many of them in a
> reasonably small space and I would need them all to be viewable on a
> single monitor (by switching).
>
> One monitor, keyboard and mouse would probably do for them all. Anyone
> aware of a good-value KVM solution for this? An 8-way would be enough.
> Some sort of power distribution would be a bonus. Second hand would be
> OK. Cheap components would be a double bonus.
I'd be thinking more in terms of network conenction for day to day
access. The problem is that both HDMI and USB are a bit too smart
to make this kind of thing easy - there is constant two-way
communication between the devices so a layer of emulation is needed
to give the attahed hosts something to talk to while they are
disconnected from the real peripherals. The older PS/2/VGA KVM
switches had it a lot easier in this regard.
For initial set-up and emergency access (if it drops off the network)
my preference would be for a serial console hooked up to a console
server (or a serial access server - they're the same thing). Those
aren't cheap new either but if you keep an eye on ebay or similar
for a few weeks you'll be able to find a used one going for a song,
just don't expect to be able to go out and buy one today for sane
money. I picked up a Lantronix 32 port model for £1 seven or
eight years ago (plus £10 P&P) and while it's never been more than
a third full it's given spectacular service for the money.
Just be sure you are comfortable on a serial line, i.e. a bare
command prompt: Unix old hands will feel perfectly at home but if
you want everything graphical from the get-go you will find yourself
lost.
--
Andrew Smallshaw
and...@sdf.lonestar.org
Martin Gregorie
Sep 13, 2015, 9:50:52 AM9/13/15
to
On Sun, 06 Sep 2015 18:00:50 +0100, James Harris wrote:
> Any of you guys already done this?
>
I wouldn't do it that way.
>
Ethernet is my preferred solution: I run my RPi headless as a normal host
on my LAN and SSH into it from whatever bigger box I'm sitting in front
of. If I wanted a GUI on it, it would be equally simple to do that over
the LAN.
If you need a lot of RPis, put them all in a common case/rack together
with an Ethernet hub (16-port switches are available from under £20 at
Ebuyer) and a common PSU (5v 26A regulated PSUs from £35.00 at Power
Supplies Online http://www.powersuppliesonline.co.uk/) and you can talk
to as many of them as you want simultaneously via SSH, VNC or whatever.
Or you might see if anybody has ported the Beowulf clustering system to
the RPi yet - that could be fun to play with.
--
martin@ | Martin Gregorie
gregorie. | Essex, UK
org |
David James
Sep 13, 2015, 10:24:27 AM9/13/15
to
On Sun, 13 Sep 2015 13:48:58 +0000, Martin Gregorie wrote:
>
> Or you might see if anybody has ported the Beowulf clustering system to
> the RPi yet - that could be fun to play with.
It has been done - see, for example, http://coen.boisestate.edu/ece/
>
> Or you might see if anybody has ported the Beowulf clustering system to
> the RPi yet - that could be fun to play with.
raspberry-pi/
Martin Gregorie
Sep 13, 2015, 1:44:33 PM9/13/15
to
is great too. Bookmarked.
I did have a search for the Beowulf mother lode (or should that be
Grendel?) before asking but didn't get far, partly because the saga is
much more interesting to the Internet at large and partly because
beowulf.org seems to be devoted to a mailing list, its archives and, errm,
nothing else. I didn't see anything useful in Wikipedia either.
Do you know if there is a central reference point for Beowulf downloads,
update news, etc?
Alan Adams
Sep 13, 2015, 2:23:52 PM9/13/15
to
In message <slrn3vfsmvas...@sdf.lonestar.org>
from computer A to B, A gets a disconnection from the USB devices.
Actually that is what is needed, otherwise the keyboard and mouse
could end up controlling all the computers simultaneously. It does
mean I don't want to run the printer through it, otherwise there's a
significant chance I will start something printing, then switch
computers and disconnect the print stream in mid-flow.
> For initial set-up and emergency access (if it drops off the network)
> my preference would be for a serial console hooked up to a console
> server (or a serial access server - they're the same thing). Those
> aren't cheap new either but if you keep an eye on ebay or similar
> for a few weeks you'll be able to find a used one going for a song,
> just don't expect to be able to go out and buy one today for sane
> money. I picked up a Lantronix 32 port model for £1 seven or
> eight years ago (plus £10 P&P) and while it's never been more than
al...@adamshome.org.uk
http://www.nckc.org.uk/
Andrew Smallshaw <and...@sdf.lonestar.org> wrote:
> On 2015-09-06, James Harris <james.h...@gmail.com> wrote:
>> I fancy setting up a few Raspberry Pis with different configurations.
>> Their small size would make them ideal for having many of them in a
>> reasonably small space and I would need them all to be viewable on a
>> single monitor (by switching).
>>
>> One monitor, keyboard and mouse would probably do for them all. Anyone
>> aware of a good-value KVM solution for this? An 8-way would be enough.
>> Some sort of power distribution would be a bonus. Second hand would be
>> OK. Cheap components would be a double bonus.
> I'm a bit late into this discussion but as others have already said
> I'd be thinking more in terms of network conenction for day to day
> access. The problem is that both HDMI and USB are a bit too smart
> to make this kind of thing easy - there is constant two-way
> communication between the devices so a layer of emulation is needed
> to give the attahed hosts something to talk to while they are
> disconnected from the real peripherals. The older PS/2/VGA KVM
> switches had it a lot easier in this regard.
I'm using a VGA/USB 4-port switch. On that, if I change the display
> On 2015-09-06, James Harris <james.h...@gmail.com> wrote:
>> I fancy setting up a few Raspberry Pis with different configurations.
>> Their small size would make them ideal for having many of them in a
>> reasonably small space and I would need them all to be viewable on a
>> single monitor (by switching).
>>
>> One monitor, keyboard and mouse would probably do for them all. Anyone
>> aware of a good-value KVM solution for this? An 8-way would be enough.
>> Some sort of power distribution would be a bonus. Second hand would be
>> OK. Cheap components would be a double bonus.
> I'm a bit late into this discussion but as others have already said
> I'd be thinking more in terms of network conenction for day to day
> access. The problem is that both HDMI and USB are a bit too smart
> to make this kind of thing easy - there is constant two-way
> communication between the devices so a layer of emulation is needed
> to give the attahed hosts something to talk to while they are
> disconnected from the real peripherals. The older PS/2/VGA KVM
> switches had it a lot easier in this regard.
from computer A to B, A gets a disconnection from the USB devices.
Actually that is what is needed, otherwise the keyboard and mouse
could end up controlling all the computers simultaneously. It does
mean I don't want to run the printer through it, otherwise there's a
significant chance I will start something printing, then switch
computers and disconnect the print stream in mid-flow.
> For initial set-up and emergency access (if it drops off the network)
> my preference would be for a serial console hooked up to a console
> server (or a serial access server - they're the same thing). Those
> aren't cheap new either but if you keep an eye on ebay or similar
> for a few weeks you'll be able to find a used one going for a song,
> just don't expect to be able to go out and buy one today for sane
> eight years ago (plus £10 P&P) and while it's never been more than
> a third full it's given spectacular service for the money.
> Just be sure you are comfortable on a serial line, i.e. a bare
> command prompt: Unix old hands will feel perfectly at home but if
> you want everything graphical from the get-go you will find yourself
> lost.
--
Alan Adams, from Northamptonshire
> Just be sure you are comfortable on a serial line, i.e. a bare
> command prompt: Unix old hands will feel perfectly at home but if
> you want everything graphical from the get-go you will find yourself
> lost.
--
al...@adamshome.org.uk
http://www.nckc.org.uk/
David James
Sep 15, 2015, 8:03:40 PM9/15/15
to
I only know of that cluster because your posting triggered a vague
recollection of having seen something about a Raspberry Pi cluster in the
past.
I think I found that one by Googling for "Raspberry Pi cluster" or perhaps
"Raspberry Pi cluster beowulf" - there seemed to be other people who had
made clusters from Raspberry Pi's too.
DisneyWizard the Fantasmic!
Sep 17, 2015, 11:39:10 AM9/17/15
to
Who is up for designing a pair of scalable plug-in KVM-over-Ethernet
plug in modules for Pi stacks?
Pi-side dongle with Ethernet and dual power (USB b + legacy barrel) on
one side, with
HDMI input, USB b power to Pi, and perhaps an Ethernet-thru port for the
Pi, with usb mouse/keyboard control input as a dongle, paired with a
User-side dongle accepting legacy PS2 mice/keyboard as well as USB
mice/keyboard, dual power and HDMI output?
Most setups would have a single User-side dongle and multiple Pi-side
modules, but would be able to accommodate several User-side dongles
(useful in educational configurations.)
That would satisfy monitoring the start-up.
I am plugging in my pair of Pis to a monitor which accepts up to three
HDMI inputs, swapping the keyboard/mouse USB cables when needed, but
primary control of each is via Ethernet PuTTY shell and Xming-windows
from a laptop, with more than satisfactory results. Reboots are done in
the PuTTY command line and I have faith the session can be restarted
after reboot. So I rarely need the TV. (save the occasional display of
traffic or weather html pages I wrote specifically for my Pi) …and a
clutter of mice. Yet, I still prefer two RPis headless.
The R-Pis each allow several students to log-in simultaneously over
Ethernet (using donated e-waste laptops) to test scripts, while the
instructor laptop runs top to keep an eye on endless loops.
--
All ladders in the Temple of the Forbidden Eye have thirteen steps.
There are thirteen steps to the gallows, firing squad or any execution.
The first step is denial... Don't be bamboozled:
Secrets of the Temple of the Forbidden Eye revealed!
Indiana Jones™ Discovers The Jewel of Power!
visit —(o=8> http://disneywizard.com/ <8=o)— visit
- better to learn by mistakes of others, - Wiz.
- erroneous examples as provided, - Wiz.
- than to learn by mistakes made for oneself. - Wiz.
- A bakers dozen out of 12 Wizards agree: "And far less painful. - Wiz."
All larders in the Temple of the Forbidden Eye rung a bakers dozen true.
There are thirteen steps to the tallows, firing square or salivation.
The first step is dental... Don't be bamboo skewered:
Secrets of the Temple of the Forbidden Eye revealed!
Indiana Jones™ Discovers The Jewel of Power!
visit —(o=8> http://disneywizard.com <8=o)— visit
plug in modules for Pi stacks?
Pi-side dongle with Ethernet and dual power (USB b + legacy barrel) on
one side, with
HDMI input, USB b power to Pi, and perhaps an Ethernet-thru port for the
Pi, with usb mouse/keyboard control input as a dongle, paired with a
User-side dongle accepting legacy PS2 mice/keyboard as well as USB
mice/keyboard, dual power and HDMI output?
Most setups would have a single User-side dongle and multiple Pi-side
modules, but would be able to accommodate several User-side dongles
(useful in educational configurations.)
That would satisfy monitoring the start-up.
I am plugging in my pair of Pis to a monitor which accepts up to three
HDMI inputs, swapping the keyboard/mouse USB cables when needed, but
primary control of each is via Ethernet PuTTY shell and Xming-windows
from a laptop, with more than satisfactory results. Reboots are done in
the PuTTY command line and I have faith the session can be restarted
after reboot. So I rarely need the TV. (save the occasional display of
traffic or weather html pages I wrote specifically for my Pi) …and a
clutter of mice. Yet, I still prefer two RPis headless.
The R-Pis each allow several students to log-in simultaneously over
Ethernet (using donated e-waste laptops) to test scripts, while the
instructor laptop runs top to keep an eye on endless loops.
All ladders in the Temple of the Forbidden Eye have thirteen steps.
There are thirteen steps to the gallows, firing squad or any execution.
The first step is denial... Don't be bamboozled:
Secrets of the Temple of the Forbidden Eye revealed!
Indiana Jones™ Discovers The Jewel of Power!
visit —(o=8> http://disneywizard.com/ <8=o)— visit
- better to learn by mistakes of others, - Wiz.
- erroneous examples as provided, - Wiz.
- than to learn by mistakes made for oneself. - Wiz.
- A bakers dozen out of 12 Wizards agree: "And far less painful. - Wiz."
All larders in the Temple of the Forbidden Eye rung a bakers dozen true.
There are thirteen steps to the tallows, firing square or salivation.
The first step is dental... Don't be bamboo skewered:
Secrets of the Temple of the Forbidden Eye revealed!
Indiana Jones™ Discovers The Jewel of Power!
visit —(o=8> http://disneywizard.com <8=o)— visit
rickman
Sep 18, 2015, 8:40:53 AM9/18/15
to
On 9/17/2015 11:38 AM, DisneyWizard the Fantasmic! wrote:
> Who is up for designing a pair of scalable plug-in KVM-over-Ethernet
> plug in modules for Pi stacks?
> Pi-side dongle with Ethernet and dual power (USB b + legacy barrel) on
> one side, with
> HDMI input, USB b power to Pi, and perhaps an Ethernet-thru port for the
> Pi, with usb mouse/keyboard control input as a dongle, paired with a
> User-side dongle accepting legacy PS2 mice/keyboard as well as USB
> mice/keyboard, dual power and HDMI output?
> Most setups would have a single User-side dongle and multiple Pi-side
> modules, but would be able to accommodate several User-side dongles
> (useful in educational configurations.)
>
> That would satisfy monitoring the start-up.
>
> I am plugging in my pair of Pis to a monitor which accepts up to three
> HDMI inputs, swapping the keyboard/mouse USB cables when needed, but
> primary control of each is via Ethernet PuTTY shell and Xming-windows
> from a laptop, with more than satisfactory results. Reboots are done in
> the PuTTY command line and I have faith the session can be restarted
> after reboot. So I rarely need the TV. (save the occasional display of
> traffic or weather html pages I wrote specifically for my Pi) …and a
> clutter of mice. Yet, I still prefer two RPis headless.
> The R-Pis each allow several students to log-in simultaneously over
> Ethernet (using donated e-waste laptops) to test scripts, while the
> instructor laptop runs top to keep an eye on endless loops.
I'm not completely clear on what you are suggesting. Are you thinking
> Who is up for designing a pair of scalable plug-in KVM-over-Ethernet
> plug in modules for Pi stacks?
> Pi-side dongle with Ethernet and dual power (USB b + legacy barrel) on
> one side, with
> HDMI input, USB b power to Pi, and perhaps an Ethernet-thru port for the
> Pi, with usb mouse/keyboard control input as a dongle, paired with a
> User-side dongle accepting legacy PS2 mice/keyboard as well as USB
> mice/keyboard, dual power and HDMI output?
> Most setups would have a single User-side dongle and multiple Pi-side
> modules, but would be able to accommodate several User-side dongles
> (useful in educational configurations.)
>
> That would satisfy monitoring the start-up.
>
> I am plugging in my pair of Pis to a monitor which accepts up to three
> HDMI inputs, swapping the keyboard/mouse USB cables when needed, but
> primary control of each is via Ethernet PuTTY shell and Xming-windows
> from a laptop, with more than satisfactory results. Reboots are done in
> the PuTTY command line and I have faith the session can be restarted
> after reboot. So I rarely need the TV. (save the occasional display of
> traffic or weather html pages I wrote specifically for my Pi) …and a
> clutter of mice. Yet, I still prefer two RPis headless.
> The R-Pis each allow several students to log-in simultaneously over
> Ethernet (using donated e-waste laptops) to test scripts, while the
> instructor laptop runs top to keep an eye on endless loops.
the Ethernet connection could be used to multiplex the user side dongle
between multiple Pis? It seems rather a busy device, likely another rPi
equivalent in complexity.
--
Rick
Rob Morley
Sep 18, 2015, 9:27:01 AM9/18/15
to
remote monitoring and control independent of the operating system.
Martin Gregorie
Sep 18, 2015, 2:44:38 PM9/18/15
to
monitor plus an Ethernet hub/switch connecting all the RPIs together.
Use the one with keyboard etc to login to the other headless RPis.
rickman
Sep 18, 2015, 3:09:49 PM9/18/15
to
that actually plugs into the HDMI/USB connectors to emulate the physical
devices.
--
Rick
James Harris
Sep 18, 2015, 3:17:01 PM9/18/15
to
"rickman" <gnu...@gmail.com> wrote in message
news:mthne9$pjl$1...@dont-email.me...
>> Put that way, it sounds very like an RPi with USB keyboard+mouse +
>> HDMI
>> monitor plus an Ethernet hub/switch connecting all the RPIs together.
>>
>> Use the one with keyboard etc to login to the other headless RPis.
>
> Exactly. Unless there is some advantage to having a device on the pi
> that actually plugs into the HDMI/USB connectors to emulate the
> physical devices.
Sure. Remote desktop or VNC etc can only work on a running OS and, what
is more, a running OS which has suitable apps. For bare-metal
programming, OS development and to see what's happening in the boot
process you need access to the real inputs and outputs.
James
news:mthne9$pjl$1...@dont-email.me...
> On 9/18/2015 2:42 PM, Martin Gregorie wrote:
...
>> Put that way, it sounds very like an RPi with USB keyboard+mouse +
>> HDMI
>> monitor plus an Ethernet hub/switch connecting all the RPIs together.
>>
>> Use the one with keyboard etc to login to the other headless RPis.
>
> Exactly. Unless there is some advantage to having a device on the pi
> that actually plugs into the HDMI/USB connectors to emulate the
> physical devices.
is more, a running OS which has suitable apps. For bare-metal
programming, OS development and to see what's happening in the boot
process you need access to the real inputs and outputs.
James
Rob
Sep 18, 2015, 5:35:46 PM9/18/15
to
install VMware ESXi and you can do all the "bare metal programming",
OS development etc that you like and have access to consoles over the
network.
James Harris
Sep 18, 2015, 6:19:42 PM9/18/15
to
"Rob" <nom...@example.com> wrote in message
news:slrnmvp0th...@xs9.xs4all.nl...
was not close enough.
I just looked for VMWare ESXi and found, in common with other VMWare
products that it is hard to understand. I am not sure what the
difference is between Vsphere and ESXi, for example. I know that Vsphere
is a hypervisor but the video describing it spoke of installing ESXi.
Two names for the same thing?
ESXi seems to be a type 1 hypervisor. Doesn't that mean that it has to
run on a Raspberry Pi in order to emulate a Raspberry Pi?
If I installed ESXi (or some other VMWare product) on an Intel/AMD
machine how are you suggesting I get that to emulate a Raspberry Pi
accurately?
James
Rob
Sep 19, 2015, 2:48:35 AM9/19/15
to
I presume when you want to teach about programming it does not matter
if the platform is Raspberry or PC. What ESXi gives you is a large
number of virtual Intel (PC) machines on a single box, and the way
to monitor it all via the network. You can see the console and input
keyboard/mouse input over the network. And the virtual machines of
course also have network so you can do SSH or VNC just as well.
This suggestion was just meant as a solution to the original problem
of setting up some system where multiple users in a classroom should
be able to work on a computer with someone monitoring their activity,
not a solution to the problem that was described in the first post
where already the assumption was made that it would be done on RPi
and some hardware was required to switch their HDMI/USB connections
onto a monitoring station.
mm0fmf
Sep 19, 2015, 3:13:33 AM9/19/15
to
On 18/09/2015 23:19, James Harris wrote:
>
> If I installed ESXi (or some other VMWare product) on an Intel/AMD
> machine how are you suggesting I get that to emulate a Raspberry Pi
> accurately?
>
Yes. How do you think the software in ARM based phones gets designed and
>
> If I installed ESXi (or some other VMWare product) on an Intel/AMD
> machine how are you suggesting I get that to emulate a Raspberry Pi
> accurately?
>
written? How do you think the software for ECUs gets written? How do you
think car dashboard display software gets written?
All of this stuff starts on accurate simulations of not just the CPU but
large amounts of the silicon is simulated (in software) either as cycle
accurate models for accurate bus simulation, or a loosely timed models
which approximate bus performance or untimed models which allow software
to be developed and tested.
Software simulations can be produced 18-24months before silicon is
available and gives designers a huge startup boost. As soon as silicon
is produced, code can be moved from simulation to hardware for real
world testing.
James Harris
Sep 19, 2015, 6:15:04 AM9/19/15
to
"Rob" <nom...@example.com> wrote in message
news:slrnmvq1a2...@xs9.xs4all.nl...
specific Raspberry Pi hardware. I think you are mixing my requirements
up with someone else's.
> I presume when you want to teach about programming
the post by "DisneyWizard"?
> it does not matter
> if the platform is Raspberry or PC. What ESXi gives you is a large
> number of virtual Intel (PC) machines on a single box, and the way
> to monitor it all via the network. You can see the console and input
> keyboard/mouse input over the network. And the virtual machines of
> course also have network so you can do SSH or VNC just as well.
and DosBox for such testing on a PC. ESXi sounds like another option,
though.
> This suggestion was just meant as a solution to the original problem
> of setting up some system where multiple users in a classroom should
> be able to work on a computer with someone monitoring their activity,
> not a solution to the problem that was described in the first post
> where already the assumption was made that it would be done on RPi
> and some hardware was required to switch their HDMI/USB connections
> onto a monitoring station.
James
James Harris
Sep 19, 2015, 6:19:37 AM9/19/15
to
"mm0fmf" <no...@mailinator.com> wrote in message
news:vW7Lx.488418$Dx3.3...@fx39.am4...
> How do you think the software in ARM based phones gets designed and
> written? How do you think the software for ECUs gets written? How do
> you think car dashboard display software gets written?
>
> All of this stuff starts on accurate simulations of not just the CPU
> but large amounts of the silicon is simulated (in software) either as
> cycle accurate models for accurate bus simulation, or a loosely timed
> models which approximate bus performance or untimed models which allow
> software to be developed and tested.
>
> Software simulations can be produced 18-24months before silicon is
> available and gives designers a huge startup boost. As soon as silicon
> is produced, code can be moved from simulation to hardware for real
> world testing.
Sure. I don't disagree but you are talking about something else. In the
paragraph above I was asking Rob how he proposed to get a good Raspberry
Pi emulation on a PC. That would be useful. It turns out he was really
thinking about someone else's problem, though, and AFIACT doesn't know
of a good Raspberry Pi emulation that will run on standard PC hardware.
If you do, of course,.....
James
news:vW7Lx.488418$Dx3.3...@fx39.am4...
> On 18/09/2015 23:19, James Harris wrote:
>>
>
>> If I installed ESXi (or some other VMWare product) on an Intel/AMD
>> machine how are you suggesting I get that to emulate a Raspberry Pi
>> accurately?
>>
>
> Yes.
"Yes"? The question was "how?". The word "Yes" doesn't answer it!
>>
>
>> If I installed ESXi (or some other VMWare product) on an Intel/AMD
>> machine how are you suggesting I get that to emulate a Raspberry Pi
>> accurately?
>>
>
> Yes.
> How do you think the software in ARM based phones gets designed and
> written? How do you think the software for ECUs gets written? How do
> you think car dashboard display software gets written?
>
> All of this stuff starts on accurate simulations of not just the CPU
> but large amounts of the silicon is simulated (in software) either as
> cycle accurate models for accurate bus simulation, or a loosely timed
> models which approximate bus performance or untimed models which allow
> software to be developed and tested.
>
> Software simulations can be produced 18-24months before silicon is
> available and gives designers a huge startup boost. As soon as silicon
> is produced, code can be moved from simulation to hardware for real
> world testing.
paragraph above I was asking Rob how he proposed to get a good Raspberry
Pi emulation on a PC. That would be useful. It turns out he was really
thinking about someone else's problem, though, and AFIACT doesn't know
of a good Raspberry Pi emulation that will run on standard PC hardware.
If you do, of course,.....
James
rickman
Sep 19, 2015, 11:31:46 AM9/19/15
to
On 9/18/2015 3:17 PM, James Harris wrote:
> "rickman" <gnu...@gmail.com> wrote in message
> news:mthne9$pjl$1...@dont-email.me...
>> On 9/18/2015 2:42 PM, Martin Gregorie wrote:
>
> ....
> "rickman" <gnu...@gmail.com> wrote in message
> news:mthne9$pjl$1...@dont-email.me...
>> On 9/18/2015 2:42 PM, Martin Gregorie wrote:
>
>
>>> Put that way, it sounds very like an RPi with USB keyboard+mouse + HDMI
>>> monitor plus an Ethernet hub/switch connecting all the RPIs together.
>>>
>>> Use the one with keyboard etc to login to the other headless RPis.
>>
>> Exactly. Unless there is some advantage to having a device on the pi
>> that actually plugs into the HDMI/USB connectors to emulate the
>> physical devices.
>
> Sure. Remote desktop or VNC etc can only work on a running OS and, what
> is more, a running OS which has suitable apps. For bare-metal
> programming, OS development and to see what's happening in the boot
> process you need access to the real inputs and outputs.
I'm divorcing from the follow on conversation and addressing this part.
>>> Put that way, it sounds very like an RPi with USB keyboard+mouse + HDMI
>>> monitor plus an Ethernet hub/switch connecting all the RPIs together.
>>>
>>> Use the one with keyboard etc to login to the other headless RPis.
>>
>> Exactly. Unless there is some advantage to having a device on the pi
>> that actually plugs into the HDMI/USB connectors to emulate the
>> physical devices.
>
> Sure. Remote desktop or VNC etc can only work on a running OS and, what
> is more, a running OS which has suitable apps. For bare-metal
> programming, OS development and to see what's happening in the boot
> process you need access to the real inputs and outputs.
Here is a block diagram of what I am reading is needed.
rPi
------+
USB |----- Keyboard
USB |----- Mouse
HDMI |----- Monitor
Pwr |---------------Wall wart
Eth |---+
------+ |
|
| +-------+ keyboard +-----+
| | |----------| |
+---| Eth | mouse | |
| Thing |----------| rPi |
+---| Eth | HDMI | |
| | |----------| |
| +-------+ +-----+
|
| +-------+ keyboard +-----+
| | |----------| |
+---| Eth | mouse | |
| Thing |----------| rPi |
+---| Eth | HDMI | |
| | |----------| |
| +-------+ +-----+
|
| +-------+ keyboard +-----+
| | |----------| |
+---| Eth | mouse | |
| Thing |----------| rPi |
+---| Eth | HDMI | |
| | |----------| |
V +-------+ +-----+
I think this is what we are describing. A main rPi (or some other
device such as a PC) with a real keyboard, mouse and display connects
via Ethernet to a series of "things" which provide the emulated mouse,
kayboard and HDMI signals to a collection of rPi (or even other
devices). The main computer requires special software to drive the
"things" via the Ethernet and the "things" will be some special hardware
which responds to the commands and emulate the three I/Os.
I didn't draw the power because that is not clear to me if it is
intended for the "thing" to channel power to the rPi or if the rPi will
power the thing. Since the keyboard/mouse will be plugged into at least
one USB port, the rPi would power the "thing".
I don't see a need for a special "thing" on the head computer which has
the physical keyboard/mouse/monitor attached. This unit is just a
computer with special software. The "things" will need a slave USB port
and an HDMI port to emulate a monitor, so I think that will require some
special hardware. I am not familiar with the HDMI spec, so I don't know
exactly what will be required for that. But otherwise, this will be not
too much different from an rPi needing enough of a CPU to handle two
Ethernet ports and being able to shuttle the HDMI graphics around.
I drew the Ethernet as a daisy chain. Perhaps that should use a
conventional star configuration with a hub/switch instead.
Another I/O that might be useful is something to force a reset, possibly
even a power switch. I run into a need for that more often than I like.
Thoughts?
--
Rick
druck
Sep 19, 2015, 2:39:18 PM9/19/15
to
On 18/09/2015 20:17, James Harris wrote:
> Sure. Remote desktop or VNC etc can only work on a running OS and, what
> is more, a running OS which has suitable apps. For bare-metal
> programming, OS development and to see what's happening in the boot
> process you need access to the real inputs and outputs.
It sounds like what you need is a serial console in order to see the Pi
> Sure. Remote desktop or VNC etc can only work on a running OS and, what
> is more, a running OS which has suitable apps. For bare-metal
> programming, OS development and to see what's happening in the boot
> process you need access to the real inputs and outputs.
boot, and to control it via a shell. You could get UART to Ethernet
converters to be able to access them remotely.
---druck
colone...@yahoo.com
Sep 21, 2015, 1:06:24 AM9/21/15
to
On Sat, 19 Sep 2015, druck wrote:
> It sounds like what you need is a serial console in order to see the Pi boot,
> and to control it via a shell. You could get UART to Ethernet converters to
> be able to access them remotely.
How remote does it need to be? Why not an old serial mouse kvm* using only
> It sounds like what you need is a serial console in order to see the Pi boot,
> and to control it via a shell. You could get UART to Ethernet converters to
> be able to access them remotely.
the serial switch part. Connect the ``master pi'' serial pins to the
switch and the other pi's to the other side. If they're all pis you won't
need voltage convertion. If the master's a PC you'll need something.
Ron
*or almost any ``mechanical'' switch.
Jonathan Lane
Sep 27, 2015, 11:31:48 AM9/27/15
to
Andrew Smallshaw <and...@sdf.lonestar.org> wrote:
> On 2015-09-06, James Harris <james.h...@gmail.com> wrote:
>> I fancy setting up a few Raspberry Pis with different configurations.
>> Their small size would make them ideal for having many of them in a
>> reasonably small space and I would need them all to be viewable on a
>> single monitor (by switching).
>>
>> One monitor, keyboard and mouse would probably do for them all. Anyone
>> aware of a good-value KVM solution for this? An 8-way would be enough.
>> Some sort of power distribution would be a bonus. Second hand would be
>> OK. Cheap components would be a double bonus.
> On 2015-09-06, James Harris <james.h...@gmail.com> wrote:
>> I fancy setting up a few Raspberry Pis with different configurations.
>> Their small size would make them ideal for having many of them in a
>> reasonably small space and I would need them all to be viewable on a
>> single monitor (by switching).
>>
>> One monitor, keyboard and mouse would probably do for them all. Anyone
>> aware of a good-value KVM solution for this? An 8-way would be enough.
>> Some sort of power distribution would be a bonus. Second hand would be
>> OK. Cheap components would be a double bonus.
> For initial set-up and emergency access (if it drops off the network)
> my preference would be for a serial console hooked up to a console
> server (or a serial access server - they're the same thing). Those
> aren't cheap new either
You can get a cheap SFF PC, install Linux or *BSD on it, and stick a
> my preference would be for a serial console hooked up to a console
> server (or a serial access server - they're the same thing). Those
> aren't cheap new either
bunch of USB serial adapters in it. I actually use my RPi B+ as a baby
console server for an old Sun pizzabox and an ASIC miner. My preferred
serial terminal client for console work is C-Kermit (available as
"ckermit" in the Debian repositories) since it's highly scriptable - you
can write a Kermit script for each individual port and set it
executable, and it supports Kermit protocol file transfers. Very handy.
> Just be sure you are comfortable on a serial line, i.e. a bare
> command prompt: Unix old hands will feel perfectly at home but if
> you want everything graphical from the get-go you will find yourself
> lost.
>
the most use out of your RPi. This makes as good an excuse to learn as
any.
--
ti...@sdf.lonestar.org
SDF Public Access UNIX System - http://sdf.lonestar.org
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