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Mac mini Sans Wires - Batteries Inside the Case
An anonymous reader writes "Running Debian (or Linux generally) on a Mac mini is old news. Silas installed rechargable batteries inside the case, delivering a couple of hours of runtime while retaining the small form factor. Although it runs fine without wires, he had to plug in the monitor to be able to show that it was really up."
Using an iMac would be a better idea, for it has a monitor already included.
Karma: Positive (probably because of superiour intellect)
Helps that Macs generally (yes, there are exceptions) run whisper quiet. Is the computer on? With a PC, just listen for the fan noise. With a Mac, hmm..can't tell, better look at the screen.
the monitor would drain the batteries like hell
Since when did nerds need a reason to do something nerdy?
This is Slashdot!
Execute? [Y/N] _
VNC is the obvious way to talk to the machine without a monitor connected...
If an external battery could be housed in a mac mini form factor external case (stacked under/ontop of the mini) I bet battery life could be equivelent or longer than a power-book (no LCD to run). Could provide some interesting low-cost remote monitoring solutions...
A Call For A New Slashdot Moderation Level!
And the use would be?
As a random act of senseless beauty.
You see, geeks do have poetry in their souls. It's just in a language they don't teach in the English department.
So -- do what appeals to you. The utility will come later.
Post may contain irony: discontinue use if experiencing mood swings, nausea or elevated blood pressure.
Bah! Real programmers don't need screens. Why, in my day we didn't even need keyboards to issue our commands. We merely bellowed at the computer and it whimpered off to do what we wanted. Honestly, the kids these days...
Not quite, cause you'd have to get it up there right before the packets you were interested in hit the network.
However -- figure out some way to parasitically power it off the wiring going to the flourescent lights, in a way that can be installed in one or two minutes, then you'd really have something.
Post may contain irony: discontinue use if experiencing mood swings, nausea or elevated blood pressure.
wait till you see my gerbil powered mini. I'm having a small problem with it though, it runs just fine in my test harness but the power seems to tail off and then die shortly after I hermetically seal the case.
Do not try to read the dupe, thats impossible. Instead, only try to realize the truth
What truth?
There is no dupe
The author says he measured 14-20W for the mac mini under load, but his 80W-Hr battery only lasted 1H:50M, implying a 40W+ power draw.
Am I missing something?
Hey, this could be the start of something big! What if he were to also install a portable screen? Maybe it could, I dunno, fold down into the top of the machine, or something. Then you could carry the computer around and do stuff with it, wherever you went, while resting it on your knee. A sort of "knee-top" compiter, though maybe there's a better name someone can think of . . .
Exactly how is the LiPo battery charged ?
0 9187
Without a proper charger, combining the energy density of a 80Wh battery with highly reactive Lithium is a recipe for disaster.
http://www.rcgroups.com/forums/showthread.php?t=2
Flourescent (adj): smelling like ground wheat.
Wow, at only 12W for the entire system? It is pretty hard to get a x86 box that low for that
cheap.
-Benjamin Meyer
Do you changes clothes while making the "chee-chee-cha-cha-choh" transformation sound?
It's a portable wireless hard drive for my laptop. Duh.
Random and weird software I've written.
I (am || can speak) French, you inconsiderate clod!
2 hours isn't to bad. Think of it as an imbedded UPS. for your system.
Preventing data loss on an accedental power outage.
Secondly if this job is done right it could help improve the life of the computer, giving the system a reliable source of power helps keep the equiptment from those little surges and dips.
Portability. 2 Hours should be enough to get you to your location without bringing the system down. So when you get to the office and quitly plug in the system to the projector bingo your keynote presintation is ready on the first page.
Convience. You have to compile your project and finish it at home. While you are driving home the code is compiling. When you get there and put power back on it is ready to test.
The Mac Mini is less of a PC and more like a Portible Laptop Computer without the extras,
If something is so important that you feel the need to post it on the internet... It probably isn't that important.
Mac Mini Surgery
I had an itch to scratch so here it is...
Earlier this week I read an article on the Debian Weekly News, about a Debian box running on 3 Watts, and it reminded me of a project that I was asked to put on the shelf some time ago. The gist of the article linked to by the DWN was that Alex Perry got to wondering how much power his Linksys switch was sucking down whilst running 24/7, and found that his Manga, an ARM based router box, not only consumed less power but was able to run full blown Debian to boot. His point was "If I am going to pay to have a switch run 24/7, I might as well have the switch be a useful server as well." Following his article the PepLink community promptly got X11 working on the Manga and Alex's website was updated with the screen shots, which I might add are quite amusing.
While I do sympathize with the original thrust of the article, I must say that the Manga's ARM is a rather diminutive processor for a desktop machine these days. So my question is why would you run a Manga as a desktop to get down to the 3 Watt mark when for just a few more Watts you can run a box with a G4 processor? Yes, I am talking about that little machine that all of my geek friends (me included) seem to be drooling over as of late. The Mac Mini!
Several months ago I was in need of finding a small but powerful computer that could be run for a long period of time on batteries and not be a burden to carry. I was looking at several embedded options from places like kontron and mini-box, when I saw an article on the Mac Mini. Looking at the limited specs for the Mac Mini on Apple's website I began to suspect that if I removed the cdrom drive I would be able to fit a "lithium-ion polymer" battery pack inside the vacated space. I say that I suspected this because Apple is lousy about posting specs about internals and stuff that your Grandparents wouldn't normally ask about. So I ran down to the local Apple store with my trusty calipers and had one of their technicians go into the back and measure the dimensions of the cdrom drive for me. The numbers that he gave me made my day, the batteries would fit! Now about power specs. Apple of course did not have the DC power specs online, and nobody I talked to at the Apple store or on the support line could get them for me. In an act of desperation I resorted to sending email to combinations of addresses like steve_at_apple.com sjobs_at_apple.com, steve.jobs_at_apple.com, etc asking for the specs. Funny enough I got a reply (No, not from Steve Jobs) from an Engineer who was quite helpful. It looked like the Mac could do it, so I decided to get one and hack on it. The Mac was dirt cheap compared to the embedded systems so it was a very limited risk approach to proceeding on the project.
I ordered the Mac, a 4GB Hitachi Microdrive, and a laptop-IDE to CF adapter. I also talked to Mike (Dr. Zhang) at SKC PowerTech, Inc, and he was kind enough to send me some batteries for evaluation. The batteries were a new design and were not yet in production, so there was a bit of a lead time on those, but at the end of two days I had the rest of the necessities at hand. First things first, I measured the out of the box power draw of the Mac Mini, which turned out to be only 12 Watts! This was better than the specs I was given. I then proceeded to remove the hard disk and replace it with the Microdrive-CF adapter setup. Then I got me a Debian (Sarge) disk *GRIN*. This was the first time I had touched a Mac, and I was pleased to find that the Debian install on the Mac was smooth and painless. After getting the system up and running, I did some stress testing on it. The testing involved running simultaneous FFT routines (like 30 of them) on 80MB data files. The system was so heavily loaded that it took about 15 minutes to log into the machine from another terminal, and another 15 minutes to get to the bash prompt. During this utter thrashing of the system the highest the power usage spiked to was 20 Watts, but it stayed around 14
Old Macs, maybe. I had to plug in a display dongle to a Mac IIci server back around 1995. But the Mac mini doesn't need one. I have a mini in my basement, and it works fine over VNC with nothing plugged into its video port.
Illiterate clod.
When I saw this, it reminded me of a very old joke I saw once.. and compelled me to post it here.
Top 12 Things A Klingon Programmer Would Say
12. Specifications are for the weak and timid!
11. This machine is a piece of GAGH! I need dual processors if I am to do battle with this code!
10. You cannot really appreciate Dilbert unless you've read it in the original Klingon.
9. Indentation?! -- I will show you how to indent when I indent your skull!
8. What is this talk of 'release'? Klingons do not make software 'releases'. Our software 'escapes' leaving a bloody trail of designers and quality assurance people in its wake.
7. Klingon function calls do not have 'parameters' -- they have 'arguments' -- and they ALWAYS WIN THEM.
6. Debugging? Klingons do not debug. Our software does not coddle the weak.
5. I have challenged the entire quality assurance team to a Bat-Leth contest. They will not concern us again.
4. A TRUE Klingon Warrior does not comment his code!
3. By filing this SCR you have challenged the honor of my family. Prepare to die!
2. You question the worthiness of my code? I should kill you where you stand!
1. Our users will know fear and cower before our software. Ship it! Ship it, and let them flee like the dogs they are!
Seeing as how old school programmers think like klingon programmers, I believe that it can be reasonably assumed that all old programmers are klingon.
I have no regrets, this is the only path.
My whole life has been "UNLIMITED BLADE WORKS"
for an Apple computer that runs on human blood!
Oh wait...
sans optical drive.
Seriously, give the guy a break. This mod probably wasn't as easy as it looks. Yes, it does have a very limited practical application due to the fact that you need a powered monitor (network access aside), but....in the long run, things like this can serve up some very innovative creations. Perhaps someone else will see this, and take it a step further, and eventually some ingenious application for a battery powered Mac Mini will appear. I say bravo, good job, and keep on tinkering.
I've often wondered why there aren't servers with batteries built in for a few minutes of power after the UPS goes down.
Apple could get especially good results from doing this because of their hardware-software integration. Imagine an xserve with ten minutes of battery power built in. Can't you see the interface where you have the computer run a script that emails you after it's been on battery power for two minutes? Imagine hooks for when battery power starts to be used, and when a clean, painless shutdown begins, or when power is restored before the battery runs out.
This would be of great value to me anyway. I know some UPS software offers this (though I'm not sure what the state of Mac-compatibility is), but Apple could surely do a better, more thorough job.
What's wrong with sans? It's a perfectly cromulent word.
One man's Funny is another man's Offtopic.
That, and you could always use both. UPS's are nice, but once they fail, wouldn't you like another few hours? (Especially on a cheap UPS where plugging a monitor into it will drain the battery in a few mins)
Pain lasts, kid. Its how you know you're alive. Sometimes I think this growing up thing is just pain management-TheMaxx
"Although it runs fine without wires, he had to plug in the monitor to be able to show that it was really up."
Actually, the mac is both dead and alive until the monitor is plugged in - at which time the mac's probablility wave instantaneously settles in at its definite and final value...that is until the batteries run out, then it's a $500 doorstop.
One of the things I tend to use the battery in my laptop for most is to keep the thing on when I move from one room to the other in the house and then plug in again. Seems like a sensible thing someone would want to do with a mini, to go from a desk in a study over to the bedroom or to the stereo to play some music for a while without having to shut down and restart.
___
Cogito cogito, ergo cogito sum.
you forgot to add "that's slower than an external firewire enclosure"
Try with Mac OS X 10.3 or later. If there are no display devices on-line the window server will create a virtual framebuffer.
In Tiger, Mac OS X 10.4, fast user switching gets a related feature. When a user session is switched off-screen, if a screen watching program such as OSXvnc-server is running, the off-screen session will get a virtual framebuffer so that it can be remote-operated while another user session or a login window is on the hardware console.
Try running OSXvnc.app, for example, and switching users. A remote VNC viewer will be able to connect to the session switched off-screen, so you can continue working from a remote location. When you set this up, make sure you set up a password for access and take the usual security precautions for a remote-controlled system.
To address questions asked here on Slashdot. The main purpose of this project was to build a wearable debian box. We had a 2 square inch VGA LCD heads up display that we were using. Also we had toyed around with Festival to read output to the user. The application did not require any user input, so no keyboard was nessasary. If someone wanted user input one could use bluetooth and a Linux PDA to run ssh or VNC. Also I have seen some IR remote controls that have a full keyboard (Do a Google search on CarPC's and remote controls), so user input is not out of the question.
Also several people were talking negativly about the battery life. My run time test was conducted under heavy load so the Mac Mini was pulling around 14-20W at the time. The device I used for measuring the power was a Watts Up Pro which was specificly designed for measuring the power draw on consumer electronics, so the readings are accurate. Bear in mind that these batteries are preproduction prototypes that were sent to me for evaluation, and SKC Films informed me after I recieved them that they would not perform optimally do to a mistake in that batch. They also offered to make me another batch, which I declined as my application only needed about 45min runtime and the ones I already had would do fine for proof of concept. The point here is that with further work the battery life can be inproved. Simply using CPUFreq in the Linux Kernel will help strech out the battery life a good deal. To address concerns someone brought up about charging the Li-ion batteries, A power supply with a current limiting knob _is_ a safe method of charging the batteries. The chargers that are designed for charging Li-ion batteries, say for instance in cell phones, do just that. I have recharged my battery pack just fine using a Topward power supply set to 20VDC and limited the current to about 50mA and the batteries didn't even get warm let alone explode in my face ;0).
Granted my application was very specific, but this could be used for lots of things. Slashdot has already mentioned quite a few. How about this one:
A portable compute brick. In a lab setting one might need to take a part of a Mosics cluster from one lab bench to another to collect and process data. Having a built in UPS on the Mac Mini with a Wifi network interface allows you to move the compute node physicly without having to first remove the node from the cluster and migrate all of it's processes off the node. Please note that Wireless comunications with the Mac Mini need to use a USB or Firewire Wifi card because the Mac airport card uses the broadcom chipset, which Linux users have learned to hate with a passion. Before someone mentions NDISWrappers I would like to state the obvious Mac is non-X86 and the binary drivers that are used with NDIS are compiled for X86.
"Why do this?" was also asked. My response...
I am a Geek, and it was fun!
Cheers,
Silas Bennett
P.S. My uname should read Fuzzy_The_Quantum_Duck but Slashdot didn't like the last 2 characters...