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Sometimes you just want a break.  Maybe you have a tech job and you don’t want to come home to “help desk” calls.  Maybe you are sick of your cousin getting viruses because he surfs unsavory websites.  I have a few subtle solutions to make these calls fewer and further between.

www.geekstogo.com – If your friend/relative has more time than money and hopefully a second computer, this website is awesome!  It is a forum filled with incredibly smart people who are glad to walk anyone through the process of fixing a virused computer.  The only thing they ask is that the person LISTENS to them very carefully, follows directions and does try to jump ahead.  These guys use a bunch of free, downloadable tools to solve problems in a methodical fashion.  One of my favorite tools from that site is “Combofix.exe”.  That tools digs much deeper than Malwarebytes and Hijackthis can possibly dig.  One of the most valuable pages on their site is the Malware and Spyware Cleaning Guide.

www.lmgtfy.com – Let me Google that for you is the ultimate in smart allelic responses to easy and downright stupid questions that people should know better than to ask you.  It’s simple but effective.  Someone asks you a question like, “What is Geordy Rostad’s tech blog called?”.  So in response, you want to send them a message that it would be easier to figure it out for themselves than to ask you this question.  This is where lmgtfy comes in.  Go to the site and put in your query.  A link will be generated.  Send them to this link and they will see animation of going to Google and slowly typing in the query.  Then they will be directed to the real Google results.  They would have to be pretty dense not to get the message.  Here is an example: what was the first .com registered?

logmein – If you can’t shurk your duties to be the family’s tech support sucker, then you probably need SOME sort of remote login agent to at least avoid a pointless car ride.  Logmein has a free version that can be installed on any Mac or PC.  It allows you to remotely log in, even from your cell phone or iPod Touch, and diagnose many problems without leaving your couch.  It does get a little shaky when you are dealing with a nasty spyware infection that is using up all the bandwidth but when someone is asking how to do some specific task and you don’t feel like walking them through tedious steps, you can jump on with logmein and make short work of the issue.  I used to use gotomypc but logmein has a free version.  It doesn’t support printing or drag and drop on the free version but who really cares for our purpose here?

Logmein ALSO has an excellent secondary use.  What if you want to secure your network but still need to be able to access it for troubleshooting?  You may not want to expose an SSH port on your router to the outside.  This is where logmein comes in handy.  Logmein to your desktop on the private subnet and then SSH from there.  This way, you can run a network with minimal or even NO exposed public ports.  Logmein uses a 256bit SHA encryption and I have yet to hear of an exploit or vulnerability for logmein or gotomypc.

1-900-call-me-lots – If you REALLY can’t discourage your friends and family from calling you, maybe it’s time to monetize your efforts.  Why not change your cell phone to a 1-900 number?  This will keep your calls shorter than usual and have the side-effect of discouraging telemarketers from disturbing you.  If they still insist on calling you, you’ll be happy to take their calls and laughing all the way to the bank.

P.S. if you are my friend or family and you are actually bothering to read this then this is certainly not directed at you.  You are hereby granted a few more freebies…

Using iPod headphones with the HTC EVO 4G

I always carry my iPod Touch with me so I can listen to podcasts.  With the Touch, I also have the Apple Earphones with Remote and Mic with me.  These are not the most durable headphones and perhaps aren’t the best sound quality but they are definitely the best match to the iPod Touch because they allow me to control the iPod while it’s in my pocket.  I can stop/play, adjust the volume, etc right from the little 3-button mic/remote.

Since I always have them with me, I decided to see if they would work on my new EVO.  Do they work?  Sure, sort of.  There is a thread on Android Forums that goes into detail about specific functions of the headphones working or not.  But my findings are that the mic and headphones DO in fact work.  The middle button for start/play/hangup also seems to work.  The plus and minus button do not seem to work for me.  Lastly, I found that the volume is way too quiet for me to use these headphones as a headset in the car on the freeway.  I listen to my iPod in the same situation all the time with no trouble but when plugging them into my EVO, I couldn’t hear the other caller well at all.

Update 7/13/2010: My previous iPod headphones find kicked the bucket and I opened up a new pair.  I can now hear the other caller perfectly.  They work just fine for this application so I can wholeheartedly recommend them.  If you carry both devices in your pocket, the iPod headphones are a no brainer.

Complaints about the Sprint Evo “4G”

Don’t get me wrong, I love my new phone but here are a few of the things I DON’T love about it that I’ve found in the last few days.  In no particular order, here is my list of nitpicks:

My iPod Touch browser seems quicker – With a 1GHz Snapdragon, I was expecting big things.  It’s not bad at all but it doesn’t blow away my 2G iPod Touch.  That being said, the screen on the EVO DOES blow away the one on the touch.  I’d expect this much though because it’s a newer device.

My iPod keyboard seems smarterThe problem is that the Android keyboard thinks it’s smarter.  It tries to do more auto correction and completion than the iPod does.  There may be a way to tweak some of this behavior but I haven’t looked that deep yet.

4G coverage sucks at least it is in my area yet I’m still charged $10/mo extra for it.  This was NOT disclosed to me at the time I reserved the phone.  I only found out shortly before I activated the phone.  Furthermore, it doesn’t seem to reconnect to 4G very consistantly.  What I mean is that when I first connec to 4G, it will sometimes connect but even in an area where the signal is strong, once the 4G drops, I’ve yet to see it reconnect on it’s own.

I was under the impression that the mobile hotspot would be a free featureStupid me.  Why would I possibly expect them to give away a feature that they can charge for?

4G was supposed to work simultaneously with voice – It was my understanding that I would be able to surf the web or run a mobile hotspot simultaneously with a voice call.

You have to have 4G on to use the mobile hotspot – This really kind of sucks since the 4G service is currently so spotty around here.  I thought my wife would FINALLY be able to replace her ancient flip phone and her Verizon Mifi with this one device.  Not today…

Speedtest fail When I ran the mobile hotspot and did a speedtest from my iPod Touch, I got 16Kbps down and 892kbps up.  BOTH of these scores are absolutely pitiful but the 16kbps is worse than the lousy T-mobile GPRS aircard I got stuck in a contract with for a year.  I though THAT was bad but at least it was dependable and had good coverage.

Sense UI lacks refinement – The HTC Sense UI is very good and has features that put the IOS to shame BUT it’s not quite as polished.  One example is when I try to thumb between homescreens sometimes I will “catch” on a widget accidentally.  This would never happen on IOS.  I think Android/Sense UI are far more powerful than IOS but IOS is far more intuitive and user friendly right out of the box.  Argue if you like but which device would YOUR grandmother or a 4 year old have an easier time learning?

Non-existent standards – This phone features a micro HDMI port. Have you ever seen a micro HDMI cable or adapter?  Nah, me either…

No skype – I was really surprised that Skype hasn’t been released for this platform yet.  It’s disappointing since I use it for international calls to Canada.  I thought it would also be ideal because of the true multitasking too.  Hopefully when it finally arrives it can be used as a home screen widget.

Market Place woes – The market place is great because they allow anything but also horrible for the same reason.  There is a ton of garbage in there including unfinished apps, beta(abandoned) apps and fart apps.  I found one today called “Do not buy this app”.  Can’t they clean this crap out?  Would it really be that hard?

I firmly think that all of these problems I’ve mentioned are quite fixable and will probably be worked out in the first few months.  The exception being the Market Place.  I think it’s the wild wild west when it comes to vetting out good apps.  They have opened the flood gates to compete with Apple’s claim of 100,000 apps but they’ve ended up with 75% junk apps that would never have made it into iTunes in the first place.  That being said, I like that fact that Metasploit on Android without rooting is on the horizon and there are a stack of NES/SNES emulators available.  The fact that iTunes blocks applications like that is fairly irritating.  I also like the fact that I never have to plug the phone into my computer to load music, docs, calender/email sync, etc.  That being said, both the iPod Touch and HTC EVO 4G will be SHARING spacing in my pocket for the foreseeable future.

I have a huge arsenal of Roombas.  I think the count is up to 3 400 series Roombas, 1 500 series Roomba, 1 Dirt Dog and 2 Scoobas.  I love having lots of these robots to clean and vacuum my house and houses that I sell too.  As a result, I’ve gone through a LOT of batteries.  What I’ve started to do is write dates on the battery of when I purchase them.  If there is anything else special or substantial(such as used or li-ion) about the battery, I’ll write that on it too.

Looking to gain more run time and a longer cell life, I’ve tried out several Lithium Ion battery packs.  If you’ve shopped for these, you’ll know that they are substantially more expensive than the plain NiMH batteries.  I’m here to tell you that they are NOT worth the extra money.  If I could buy a Lithium Ion pack for a 400 series Discovery for the same price as a NiMH, I might do that but otherwise I would advise against it.  There are specifics for each robot as to why they are not well suited for use with a Lithium Ion pack.  I will detail that below but the long and short of it is that the Roomba charging circuits are NOT designed to optimally charge a Lithium Ion pack.  Most of the time the cells are being charged to 4.3v or maybe even higher.  If you drop the peak charging voltage down to 4.2v, you gain substantially more charge/discharge cycles.  I would say 4.2v versus 4.3v would result in a 100% increase in charge/discharge cycles.

The other problem is protection circuitry.  Most(all?) of the Lithium Ion packs commercially available for the Roombas and Scooba do not have separate balancing/charging circuit boards.  They all rely on “protected” cells.  The protected cells have a circuit built in to protect them from catastrophic over charging and/or over discharging.  These protection circuits are set at the absolute upper and lower limits of the cell’s operational ranges.  They are set to protect against explosion and cell instability, not for cell longevity.  Here are more specific problems present in each of the iRobot platforms:

500 series –  The charging circuit is very touchy and is expecting specific characteristics.  If those aren’t met, you will likely get an “error 5” on the screen.  Much more likely than you would with a NiMH pack.  The internal charger also will consistently charge this pack over-voltage.  It’s supposed to be 22.5v on the input side but mine puts out 22.97v even in circuit.  I’m taking a wild guess that mine is not the only one that has this problem.  By the time you trace the voltage to the battery pack, it calculates out to over 4.3v per cell which is too high.

400 series – The 400 series is probably the best candidate for a lithium-ion battery pack but still not necessarily a good one.  Most vendors who sell these lithium-ion packs are relying on an internal cell protection circuit and the Roomba’s over discharge circuit to shut the pack down.  Neither of these circuits are actually designed for that purpose.  The Roomba’s circuitry is adjusted to optimally discharge NiMH packs and the internal cell protection is worst yet.  That is ONLY a last resort and should never be relied on to repetitively be used for that purpose.  If the cells somehow become out of balance, this can start happening a lot.  The symptom is that the Roomba won’t park or go to a red light, it will simply die in the middle of the floor and become entirely lifeless.  The power button won’t do anything until you charge it enough to be recognized.  Another problem with the 400 series is that the Li-Ion pack makes the Roomba much lighter and it seems to have a harder time making contact on the dock without the added weight holding it down.

Scooba – This one is one of the worse of all.  Personally I have a BAD habit of not taking the battery out right away when the Scooba dies.  While I was fixing a Scooba for a friend one time, I was probing around trying to diagnose a problem and found that even when the Scooba is TOTALLY off, it’s still drawing quite a bit of power.  I tested the output leg on the 78XX series regulator and found voltage there and a few other places.  The logic was all still hot and drawing power as well.  The power switch on the Scooba is essentially soft power.  This is probably the case with the Roomba too although I haven’t tested it.  The difference being the Scooba isn’t designed to dock.  Not only that, I’ve always charged the battery out of the unit in the Scooba Charging Base.  This is an extra step that I sometimes don’t have time for.  As a result, I’ll sometimes forget about it entirely and the battery will sit in the Scooba and over discharge.  Doing this a few times will surely fry a lithium ion pack and will eventually fry a NiMH even.

The bottom line is that you are far better off sticking with NiMH battery packs for the Roomba, Scooba and Dirt Dog.  I have used the Tenergy Scooba Battery with success in the past although one of my friends has had VERY mixed results with the Tenergy rechargeable AA’s.  For the Roomba, they have OEM Roomba batteries at the Renton, WA Frys for $40 which is a steal for a local store in my opinion since the list price is $69.99 or they have them on Amazon even cheaper at this link: iRobot 4905 Battery.  For the 500 series, I have had success with this Aftermarket 500 series APS Battery sold by Allergy by Gone.  If iRobot products were designed specifically for Li-Ion chemistry, I have no doubt that Li-Ion packs would perform fantastically and we would all benefit from longer run times and cell life but since they are not, I don’t think it’s a great idea to run these types of battery packs in your robots.

Mike was curious about how I felt about my new HTC Sprint Evo.  Little did he know that I would later post our conversation on my blog as an interview to share my perspective on this new phone.  I picked up my phone from Radio Shack on June 4th, 2010 at 10am.  Right away, I put in my gmail account info and was pleasantly surpised that all my contacts showed up.  I had gone to a bit of effort the other day to consolidate my contacts into the Mac address book and sync it with Google so it wasn’t exactly a shock that it worked but I tend to expect the worst lately.  Anyway, on with the interview(with links injected):

Mike says: (11:47:30 AM)
Got your new fangled phone yet?

Geordy says: (11:47:41 AM)
Yep

Mike says: (11:48:05 AM)
How is it?

Geordy says: (11:50:06 AM)
I don't really know how to use it
Geordy says: (11:50:29 AM)
I hate to say it but the iPod/iPhone is a hell of a lot easier to just pick up and use out of the box.
Geordy says: (11:50:38 AM)
I'll need some time to figure this one out
Geordy says: (11:51:05 AM)
They already sent out an OTA update to "fix" the rooting hole

Mike says: (11:53:09 AM)
Maybe the new iPhone will go on Sprint.....there's some rumors.

Geordy says: (11:53:34 AM)
I really doubt that
Geordy says: (11:54:05 AM)
Besides, I've heard the iPhone is AT&T only until at least 2011

Mike says: (11:55:08 AM)
You get 4G coverage in Kirkland?

Geordy says: (11:55:13 AM)
nope
Geordy says: (11:55:24 AM)
I've not seen it flip to 4G even once
Geordy says: (11:55:33 AM)
which pisses me off a bit
Geordy says: (11:55:41 AM)
since I pay an extra $10/mo for it now

Mike says: (11:55:54 AM)
I figured as much........what's your 3G speed like?

Geordy says: (11:56:05 AM)
I haven't done a speed test yet
Geordy says: (11:56:27 AM)
but web pages aren't exactly loading at breakneck speeds I'm sorry to say

Mike says: (11:56:35 AM)
How you like the overall size, screen etc

Geordy says: (11:57:03 AM)
The screen is totally awesome.  It absolutely blows away the screen on my iPod touch.

Mike says: (11:57:32 AM)
wow, not like ipod touch screens are that bad either

Geordy says: (11:58:19 AM)
Calling this phone a candy-bar style is kind of funny though.  I have to laugh when I imagine holding a candy bar that huge to the side of my head
Geordy says: (11:59:00 AM)
oddly though it's no bigger than my iPod touch is with the iBand case on it.
Geordy says: (12:01:04 PM)
I'll have to figure out how to get some applications on here.  Starting with that barcode reader that you have on yours

Mike says: (12:01:30 PM)
just open market, search barcode scanner

Geordy says: (12:03:13 PM)
One problem I had was when I posted a Twitter update, I didn't see the predictive text change words on me until it was too late.  My Twitter account then updates my Facebook but it there appears to be no way to delete Twitter or Facebook postings from this phone.

Mike says: (12:04:16 PM)
Took me a while to get used to that also, once used to it it's great though.

Geordy says: (12:04:17 PM)
I finally figured it out on Twitter by going to the site in the browser but on Facebook, it takes you to a special mobile Facebook site that also doesn't seem to have a way to delete erroneous posts.

Mike says: (12:05:02 PM)
In browser, go settings and uncheck 'mobile' sites
Mike says: (12:05:57 PM)
It'll take you a week to get used to that beast.....if it doesn't grow on you, you could always go back to your Palm WinMo phone, ha ha

Geordy says: (12:15:34 PM)
ugh.  no way.  I know I'll like it.  It's just like getting used to any new device.  I'm just saying I felt WAY more comfortable with the iPod Touch on day one.

Dusting off my new old IBM PC XT

IBM PC XT front view

I was at a computer recycler the other day and there it was… An original IBM XT 8088 system in nearly mint condition.  It was in the front window of “prized” old crap in this store.  I asked the guy if any of that stuff in the window is for sale and he replied, “sure, sometimes it is”.  So then I specified that I was interested in the XT.  He asked what I’d pay for it and I told him $20.  He said, “sure” and it came home in my trunk.  Luckily on the way out the store I noticed the keyboard sitting there.  I asked him if it was cool if I took it and he said it wasn’t a problem.  Later I found out that it’s a good thing I grabbed it because an AT-style keyboard wouldn’t work.

IBM PC XT inside

After bringing it home, brought it out and popped it open to check what was inside.  The system is actually fairly packed.  Someone probably spent $5,000 or so upgrading it to the point it was at.  The memory banks were full and there was an add-on memory card that had a realtime clock as well. Something else I learned was that originally these systems required you to enter the time and date every time you booted them up.  How annoying….  Looking around further, the system has an unmarked graphics card with a printer port.  I would have hoped it was a Hercules but I’m pretty sure it’s not a real one in any event.  There is a 20 megabyte Seagate MFM hard drive and a MFM controller card in there too.  Something else I learned is that IDE pretty much requires a 16-bit data bus to function at all and the 8088 has an 8-bit external bus so it can’t work with IDE without some major trickery so I’m crossing my fingers that the MFM drive still functions.  Lastly, there is a serial port card.

IBM PC XT back

I did plug it in and flip the power on.  Sounds like the hard drive spins up just fine at least.  I’m hoping that it works but I’m currently trying to hunt down an ISA VGA card to test it with.

You may ask why I bothered buying a nearly 30 year old computer.  My original plan was to part it out and build a single board 8088 to learn more about computers but I’ve since changed my mind since this one is in excellent shape.  I have a really cool old book called The 8088 Project Book by Robert Grossblatt.  It goes through the entire process of building up and programming an 8088 based computer on a breadboard.  The picture on the cover is an insane spaghetti mess of wires and breadboards.  Looks like fun but I’m not sure I’m up to the task.

My alternative plan is to use the computer as it sits an attempt to learn some 8088 assembly language in the dos environment.  Might also be fun to try some other operating systems like CP/M or Xenix if I could find copies of them.

Goodbye old phone, I'm not sorry to see you go.

June 3rd could not come soon enough.  I have been stuck on a Palm Treo 800w for what seems like over 2 years.  Sure, the Palm Treo 800w is better than the PPC6700 that it replaced but the battery life sucks, it has a terrible camera and has gotten extremely flaky lately.  As I’m talking on the phone, it opens up random applications for instance.  When i get off the phone, I generally have to close about 4-6 programs that are running.  I only originally chose the Palm 800w because it was the only phone available with irda.  I needed irda because I’m also a Realtor and the key boxes open up with Infrared.

I pre ordered my phone from Radio Shack.  I did this for several reasons.  First off, Sprint would not promise me a phone.  They said they would put my name on a waiting list but on the first day of release, the phone would be given out on a first come first serve basis.  Their previous popular phone, the Palm Pre, sold out in an hour.  Additionally, Sprint offered the phone with a $100 rebate so it ended up costing $299 at the point of sale and then they keep your money for 6-8 weeks while they decide if you’ve met their rebate criteria or not.

Radio Shack on the other hand was totally cool about it.  They said the phone is definitely mine.  All I had to do was purchase a $50 gift card at the time of reservation.  If I didn’t show up to pick up the phone on the first or second day, I would lose my reservation but still have my gift card available to use on any other purchase that I would like.  On top of that, they said I would receive a $20 credit towards any accessory purchase at the time of sale but the topper is that there is no manufacture’s rebate.  The only complaint I have overall about the process is that I was not able to opt for a 1-year contract.  I was forced into a 2 year contract.  Otherwise I had to pay $700-$800 for the phone.  I really hate to be stuck with any device for over a year but this one looks good enough to take my chances with.

I’ve had to do a bit of preparation to get ready to move to my new EVO.  First off, I needed to consolidate my contacts since I moved from Windows XP to a Mac in early 2009 so I still had things stuck in Outlook Express.  I consolidated them all to the Address Book on the Mac side now.  I also took it a step further and sync’d up address book to Google.  My hope is now that I will bring my new phone home, put in my Gmail account info and it will magically all just work.  I’ll report more on that in a few days.

It appears that the rooting community has even figured out how to root the EVO before it’s even released.  Overall, there seems to be an enormous amount of excitement over this phone.  Personally I can’t wait for the 3rd.  Amazon already has four pages of accessories available even.  Personally I have my eye on this Rubberized Hard Case for HTC EVO 4G.  It’s not quite an iBand but it looks like it’s the best available so far.

Expanding the Mattel Aquarius running man program

Original Running Man Program for the Mattel Aquarius

I’ve been playing with the first computer I received for Christmas when I was 5 years old.  It is a Mattel Aquarius.  It’s a bit obscure and was not well-received by the general public when it was new but I had many years of enjoyment from it and it really sparked my interest in computers.  Luckily I saved the manuals because there is not much documentation out there for it.  One of the first programs I entered when I was 5 was the Create A “Running Man” program.  I didn’t particularly understand how it worked back in 1983 but looking at it again, the concept is pretty easy.  It clears the screen and prints 2 stacked sprites that look like a man in one position.  Then it clears those sprites and prints 2 alternative stacked sprites one space over, then clears those.  Rinse and repeat.  To prevent the program from running so fast that you can’t see the man running, there is a subroutine called after the man is draw in a particular position that kills a bit of time.  Here is the original program:

10 PRINT CHR$(11)
20 FOR X=0 TO 38 STEP 2
30 A=12328+X+11*40: B=A+40
40 C=A+1: D=C+40
50 POKE A,21: POKE B,22: GOSUB 110
60 POKE A,32: POKE b,32
70 POKE C,23: POKE D,24: GOSUB 110
80 POKE C,32: POKE D,32
90 NEXT X
100 GOTO 20
110 FOR P=1 TO 30: NEXT P: RETURN

Modified Running Man Program for the Mattel Aquarius

I wanted to spice this program up a bit and add some color and variation.  I decided to make the man run at different speeds by randomizing the timer on the subroutine.  I added some color by having the man leave random colored rows of “dots” behind.  I know it’s not terribly innovative but I found the excercise amusing.  Here is the modified program:

10 PRINT CHR$(11)
20 FOR X=0 TO 38 STEP 2
25 IF X=0 THEN COL=INT(15*RND(1))
26 IF X=0 THEN SPD=INT(200*RND(1)+20)
30 A=12328+X+11*40: B=A+40
40 C=A+1: D=C+40
45 POKE B+1024,COL
50 POKE A,21: POKE B,22: GOSUB 110
60 POKE A,32: POKE b,32
70 POKE C,23: POKE D,24: GOSUB 110
80 POKE C,32: POKE D,32
90 NEXT X
100 GOTO 20
110 FOR P=1 TO SPD: NEXT P: RETURN

I’ve tested it on my real hardware and Virtual Aquarius now so it should work for you as shown.  If you have your own fun variations to this program or other fond memories of this computer, please post a comment down below.

Thanks to a hot tip from Hack a Day, I became the proud owner of a RFID reader for $10.  It is a Parallax branded part.  If you go to Radio Shack, you’ll probably find that it’s not marked down in the drawer but when you take it up to the cashier, it should ring up at $10. In the past, I’ve always disregarded the Parallax branded parts because I associated them with BASIC stamps which I am not to interested in since I feel like they are excessively priced considering an AVR can do all of the same stuff and more with a little fiddling.  Taking a closer look however, I see now that most of the accessories could be interfaced with any project.

On the front of the package, it has the RS part number which is 276-0032.  It is labeled “RFID Reader with tags”.  Below that it says:

  • 2400-baud serial output
  • Easy prototyping and integration
  • Includes two passive ransponder tags (yes it there is a typo on my package)

On the back side of the package it says:

  • Ideal for payment systems, inventory tracking and similar applications
  • 2400-baud serial output to a PC or other processor
  • 0.100 pin spacing for easy prototyping and integration
  • Includes 2 different passive transponder tags
  • Dual-color LEDs

Whatever the case, I opened up the package and found the reader and the two different RFID tags.  One is a donut-shaped ring that says “World Tag Unique RFID – Logistic and Industrial Transponder“.  The other tag is unmarked but appears to be a blank ID card that is ready to be printed.  I couldn’t find much info on that World Tag and there is even less on the blank card since it’s not labeled.  The only sensible thing to day here is to test it out and see what happens!

With a little help from the RFID Reader #28140 datasheet, I found that the ENABLE pin needed to be grounded to activate the antenna.  When you apply power, the LED turns green, then you ground the ENABLE pin and the light turns red.  This means the unit is ready to scan RFIDs.  I used a prolific USB-Serial adapter and booted hyperterm in a VM to capture the output of the device. I plugged a null modem cable into my serial converter so it would be easier to jumper down to my breadboard.  I wired pin 3 on the null modem cable to SOUT and pin 5 to GND.

The “numbers” that the device spits out seem to be a 12-byte ascii string of somewhat odd characters so what I get in HyperTerminal isn’t especially readable.  I did copy and paste the output into a hex editor though and it became a bit more coherent.  Reading the datasheet mentions that the first and last byte are start and stop bytes so that leaves you with 10 actual bytes of unique identifier string.  This works out to a WAY larger number of possibilities than I can comprehend(1.16252367 × 10 to the 24th to be precise).  A couple of interesting facts…  As long as I hold the card near the reader, it continues to spit out it’s string over and over.  When I pulled the tag away quickly, sometimes I’d only get a partial read but then it would usually start again at the beginning when I would put it back again.  Putting two tags near the reader at the same time seems to confuse it as I would expect.  It does fairly well in that regard though.

One thing to note is that I ran into some serious reliability issues as the voltage of my dying batteries dropped.  When they got down to three volts, the reader failed to function even though the indicator light was still bright as ever.  Plugging it into a wallwart did the trick though.

This is a bare bones reader.  What I mean is that ALL it does is read the tag and spit out the number over and over again.  It is up to whatever you plug it into to give the user tactical feedback of some nature that the card has properly been read.  IE, this reader doesn’t beep, blink, buzz etc, so they leave that part up to you.  There is also no inherent security in this device to speak of.  If someone could tap the serial line, they could obviously spoof whatever number can be read.  As far as cloning the tags, I’m not sure how it could be done but I’m sure it’s possible.  I DID try to scan various different tags I could find in my house with no success.  First one was an HID card.  I didn’t expect anything but it was worth a shot.  Also tried the rest of the cards in my wallet with no success (thankfully) and a few various inventory control tags.

Personally, for my own projects, this is a solution without a problem but these RFID tags are everywhere so it is an interesting study to see how they operate on some level.  If you want more information on this RFID reader, the datasheet is an excellent resource.  Extra RFID tags are available in low quantities from the Parallax store

Different Linux distributions for the Zipit Z2

updated 3/24/2011

The Zipit Z2 is a great little hacking platform.  There are lots of people putting out their own distributions and directions for customizing this platform.  I’m going to attempt to make a list of all of the distributions and sources that I know of at the moment.  If anyone knows of any other distros out there for the Z2, please feel free to comment.  Here is the list in no particular order:

z2lite & z2sid – Wicknix was bored and put out z2lite.  For more power, try the Debian-based z2sid in both a command line only and X11 version.  These are the latest and greatest as of my most recent update.  They require uboot which is dead simple nowadays.  Mozzwald has links to the uboot version of z2sid on his site.

Wejp’s Z2 linux – Not sure I’m calling this by it’s proper name but this one is also one of the newer ones.  I haven’t tried it out myself but I know several folks have.  Click here to check out Wejp’s Linux.

UbuntuMozzwald has recently rolled out a version of Ubuntu for the Zipit Z2.  The most exciting featured of this distro for me is that it has gcc.  It’s the only Debian-based distro with gcc working properly at the moment.  Here is the link to Mozzwald’s Ubuntu distro.  I have also provided my own installation instructions.  I also started a Ubuntu for Z2 RC1 torrent to take a bit of pressure of Mozzwald’s server.

Root Nexus – Optk1k2600 is running this one-man community project.  It is a very nice image that is a touch more polished than some of the others.  For instance, the battery meter is somewhat stable on Root Nexus vs Side-Track in my experience.  There is lots of customization that Optk1k2600 has done to tailor this distro nicely to the Zipit platform.  Follow this link for more information on Root Nexus.

Side-Track – This distro was rolled out by none other than the Iron Geek, Adrian Crenshaw.  This one is based on Root Nexus but is customized for pen-testing so it has a bunch of cool network analysis/cracking tools on it.  Not all of them are tested and functioning.  It’s not a perfect distro but it’s pretty good and probably my favorite at the moment.  Click here for more information on Side-Track for the Zipit.  Now if only we could get driftnet working…  update 3/24/2011 – Irongeek has moved on to other projects and has not been keeping this updated.  I have made side-track work with uboot though if anyone is interested in giving it a shot.

IZS2 – IZS2 is developed and maintained by Ray Dios Haque.  This distribution does not require reflashing the boot loader or any other modification to the Zipit Z2.  I have not tested this userland but it seems to be a very popular choice in the Zipit community.  Follow this link for the IZS2 homepage.

EZ2S(IZS2 enhanced) – Russell Davis has been hard at work improving his latest Z2 shell.  Russell’s distribution has the distinct advantage of not requiring the boot loader to be reflashed.  Reflashing the boot loader makes a lot of people nervous since it’s possible to brick your system.  Unfortunately, I have not had time to try EZ2S or IZS2 enhanced since I didn’t find out about them until after I had already reflashed my kernel.  I know I can always go back but I’ve been too busy with Side-Track and Ubuntu to mess with it.  IZS2e/EZ2S is a fork of IZS2 which was developed by Ray Dios Haque.  You can read more about EZ2S on Russell Davis’ blog Executing Gummiworms.  Russell also has developed some cool scripts and binaries that have improved things for Zipit Debian users.

Aliosa27 – Hunter Davis made a video showing the entire process of installing the Aliosa27 image onto your Zipit.  I have not tried this one since it seems to be one of the older distros available.  Installing the Aliosa27 image involves reflashing the bootloader so that step is similar to any of the other Debian-based userlands out there.  Here is the link to Hunter’s videoQuantumLime also has a very nice and detailed page that features installation instructions for Aliosa27’s image.

OpenembeddedOpenembedded(for the Zipit at least) appears to me to be dead. Looking at Zipit Openembedded information page it sounds like the Zipit patches are out of sync with the mainline Openembedded code and probably mostly useless now. I’m including it here for historical purposes only. I have finally figured out how to build an Openembedded image for the Zipit.  Openembedded is really powerful and allows you to pretty much roll your own distribution with whatever features you would like.  Check out my guide Building Openembedded for the Zipit Z2 for more information.  Please comment below if my assumption is inaccurate and I will update this post.

Emdebian Grip – This distribution is another “roll your own” variety like Openembedded.  Douglas Henke has some excellent, detailed instructions on his blog about how to roll your own Emdebian Grip distro. As good as the instructions are, I haven’t tried it out yet myself so I can’t comment on how good or bad it is.  Here is the main Emdebian Grip homepage.

Buildroot – Yet another roll your own root fs for the Z2.  Buildroot is another alternative to Emdebian and Openembedded.

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