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Belkin Play Max Ethernet Problems

Belkin Play Max 

HEADS UP

Unfortunately, the new Belkin Play Max that we thought was the Bee’s knees (compared to the frustrating problems encountered with the Apple AirPort Extreme last week) has turned out to have crazy problems of its own! *sigh*

The new Belkin Play Max appears to have a serious issue in supporting basic UDP protocol (and possibly other things) via its built-in Ethernet switch.

This first showed up for me when my “Teleport” program (Mac-to-Mac KM remote control) stopped working directly after installing the Belkin and using it as the main hub for our home network. At the time, I didn’t see the correlation with the Belkin and set the issue aside in my ever-overflowing, “too hard for now” bin.

A few days later though, I realized that Apple Home Sharing (iTunes etc) wasn’t working, though it had been doing so flawlessly, for months.

Long story short, switching the network back to a spare D-Link Gigabit switch fixed the problem, with both Home Sharing and Teleport! Switching back to the Belkin broke it all again. Bear in mind that this should not be involving ANY routing what-so-ever — just basic Ethernet switching on the local LAN.

I’ve done this switching around several times, just because I could and got exactly the same result every time. I can just stare at iTunes and watch the shared libraries come and go — and Teleport work, then stop working — , as I change cables, without restarting anything.  I have also tested restarting both software and power-cycling machines though, just to be doubly sure if what I’m seeing. In fact, I spent half the day on this issue.

All other networking seems to be working OK, which is pretty weird I guess, considering!

The only thing in common between Home Sharing and Teleport seems to be the use of the UDP protocol — as incredibly unlikely as that may seem, especially at only the physical layer. In fact, this actually suggests that there’s some kind of inadvertent packet filtering taking place in the Belkin. (The firewall is switched off.) But why would the firewall/router even be involved at the physical ether-switch level? That’s something only Belkin can answer I suppose.

Suspecting a (barely) possible issue at the Gigabit Ethernet level — maybe something around “gigabit jumbo frames”, which is often not supported by cheap switches — I tried forcing all the related network interfaces down to 100baseTX. But that made no difference.

So I’m afraid there’s a serious flaw in this unit, somewhere, somehow. I’m hoping its actually a firmware correctable problem and that a fix for it comes soon. But I’m not holding my breath.

Meanwhile, there’s at least one other person having trouble with Home Sharing, using a Belkin router (http://discussions.apple.com/thread.jspa?messageID=13216871). There’s others with the same problem using different brands in that thread too, so I guess this example is in no way conclusive.

I should point out that the problem with Home Sharing does NOT occur if all computers involved are connecting via the Belkin’s Wi-Fi interface. The problem only appears when cabled, Ethernet is in use — by ANY device trying to access or provide Home Sharing data on the network — and that also includes a second LinkSys WRT54g Wi-Fi access point, connected to an Ethernet port on the back of the Belkin Play Max. Naturally, the same AP works just fine if connected together with the other computers on the test D-Link ether-switch.

2011
03/14
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Tech
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Apple AirPort Extreme a Huge Letdown

A HUGE let down :(

The Apple(tm) AirPort Extreme II

[2011-03-11 heavily edited for accuracy and what not :D ]

This product looked like a real winner and the ideal upgrade to our ageing but ever faithful, LynkSys WRT54G. Only, it simply didn’t work for us at all, due in my humble opinion to poor programming design. WHAT?! From Apple?! Well… yes, apparently. I’m actually still in shock as I type this.

So what’s wrong with it?

Well, it turns out that the AE DHCP client for the WAN (Internet) port cannot handle the IP addresses offered by various modems running in half-bridge mode. The result, for those living in countries where PPPoE is not the norm — ZERO Internet connectivity, unless you’re lucky to have an arguably half baked half-bridge modem. (There have been several replies to my forum posts from people using their AE’s and Apple Time Capules with half-bridge modems successfully. However, Google seems to suggest that the majority have the same problem we experienced.)

In this specific case, when our D-Link 502T, firmware-upgraded DSL2 modem runs in half-bridge mode (in order to offer the AirPort Extreme a “proper” IP address on the internet (no Network Address Translation (NAT) — thus a ‘direct’ connection) the “IP address” and the “router” (default gateway)  address given to the AirPort Extreme are exactly the same. This is common with half-bridge mode implementations. In fact, I would argue that it’s the one thing that defines the source as a device offering a half-bridged connection.

Alas, under this condition, the AE’s internal programming decides that the IP address is invalid and falls back to a self-assigned, private IP, which is of course useless. Upgrading to the latest firmware (one x.x.1 step  up) made no difference unfortunately. (I seem to recall that even OS X on my iMac cannot cope with this, either. But I haven’t tested it recently.)

Interestingly, I was able to manually specify the exact same IP, gateway and DNS server addresses being offered by the DHCP server and guess what? It worked! But this is no solution when the IP address being offered by the ISP can change at any time.

Our ancient old LinkSys WRT54G handles this mode of operation flawlessly. Granted, it has custom firmware. But that firmware is also at least three years old. Half-bridge mode is not exactly rare — especially outside of the USA. Sure, there’s no real standard for the mode. But it’s been around for a long time now and I reckon most any modern router should handle all common variations — especially considering how completely not difficult that actually is.

I might have been prepared to settle for using the AE in bridge mode, so as to take advantage of Wireless-N and the shared hard disk or printer functions, which I did want. But alas, even over a 1Gb Ethernet link, hard disk performance was very poor. There’s also some strange problem with mounting my Apple formatted 1TB Seagate USB drive. It just doesn’t work. Again, Google reveals others with the same problem, though most seem to be OK in this instance.

So all in all, a very poor performer and, I’ll say it again, a big surprise from an otherwise excellent hardware/software developer such as Apple.

Nothing much can be done about the situation at my end. We’ll just have wait until Apple releases the AirPort Super-Mega-Duper-Extreme and fixed the couple lines of firmware source code to remedy things.

Meanwhile, we ended up with the latest offering from Belkin, with 2 USB ports for sharing a hard disk and a printer. This device seems to be working very well, with its built-in DSL2 modem to completely avoid that situation — and for a little less than the same money. (No Time Machine support though, which is a shame.)

We remain astonished, because we’re actually BIG Apple fans around here and have got ourselves thoroughly used to quoting the old, “It just works!” slogan, as well as the standard answer to frustrated Windows users, “Get a mac!” Ah well. No one is perfect.

But have you seen the new iPad 2 promo video yet? Apple hits another home run! Awesome.

2011
03/05
CATEGORY
Tech
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Curing Multiple Drive Map Weirdness in Windows

To help Google help you find this article, I should mention a few names I’ve come up for this scenario, search query names like, “multiple unwanted drive mappings”, and “windows multiple duplicate drive mappings” or even, “windows many cloned drive maps fault”.

Foreword

None of the stuff in this article actually worked out in the end. Seems that underneath all the eye candy, Windows is still uselessly poor where it counts. Save yourself a lifetime of hassle and switch to Mac. You’ll never look back. That said …

The Story

A long, long time ago, I remember having a strange problem under Windows XP with Office 97. Machines around the office would have a single drive mapping to a samba network share — say, something like …

\\server\homedir (H:)

After booting, if I opened Windows Explorer soon enough, I’d see just that one mapping, as expected. Then, if I just sat there, doing nothing but staring at ‘Explorer, after a minute or so, that same mapping would start duplicating itself under every avaialble drive letter. Something like …

\\server\homedir (E:)
\\server\homedir (F:)
\\server\homedir (G:)
\\server\homedir (H:)
\\server\homedir (I:)
\\server\homedir (J:)
... all the way down to ...
\\server\homedir (Z:)

Back then, it took ages to find the cause, which turned out to be some kind of bug in the Office 97 ‘parasite’ program, FindFast — a file indexer meant to make finding stuff quicker, which it actually did do, reasonably well, I guess. (Who on Earth forgets where they saved things though? :p) Completely removing FindFast made the problem go away back then and I hadn’t paid it the slightest thought over the ten plus years hence. (Never came across it again either, oddly enough!)

Fast-forward several major service packs of Windows XP, through Windows Vista (yikes!) and all the way up to Windows 7 (with the latest service packs as at 2011-01-01) and we find that, in true-to-themselves Microsoft form, the SAME fault still exists in the Windows7 buil-it Indexer service today. AMAZING, yet somehow not surprising. (I converted to Apple Mac as soon as they went Intel under BSD Unix — after some 20 years of Windows’ psych0-trauma’ing. To think — I used to actually believe that bugs like this were just an unavoidable part of owning a computer. I’m much wiser now though! :p)

Granted, this is one of those faults that seems to hardly ever show up anywhere on the planet — unless M$ have a secret pact with Google to remove all mention of it, somehow. But it’s not completely unheard of. I did manage to find ONE solitary post on the topic, from back in 2004 I think. Heck — it might even have be from me. (Don’t think so.)

So the fix under Windows7?

Go to the Control Panel, change the view to anything but ‘by Category’ and locate Indexing Options icon. Activate that and click the Modify button, lower left of the resulting window. Remove the tick from checkbox alongside Offline Files. (Searching for files you can’t even access? What’s with that anyway?) Problem solved.

I have to admit that I was quite astonished when this stab in the dark actually did cure the fault. Since I’ve been living with it for months (in a virtual machine I use for PCB design under Windows) and only just finally came up with this brain-storm-fluke of an idea, I thought I’d better blog about it somewhere, in hopes others with the problem can learn the answer too. Hope it helped … and that my sarcastic, cynical banter wasn’t too bad a thing to endure.

Oh no!

The problem came back. It no longer happened “just on its own”, as mentioned above. But some programs seemed to trigger it to happen again after opening the Choose File dialog box.

Suspecting the possibility of residual index data from before I disabled ‘Offline Files’ indexing, I click the Advanced button in the Index Options window and then the button to delete and rebuild the index. So far, the problem has not come back again. Yay \o/

I suppose that disabling the indexing service altogether (don’t know how in Win7 yet) might be the ultimate fix. But it seems a little ‘sledge hammer’ to me.

I Give Up

OK. I give up. It came back again the next morning. If you stumbled upon this post and did eventually find a permanent cure for this ancient incurable Windows BS bug … please do let me know by way of a comment. Thanks.

2011
01/01
CATEGORY
Tech
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ER9X-gruvin 20101111 release

ER9x-gruvin Firmware Release 2010-11-11

I’ve made a few changes/additions to my ER9X firmware.

Feature 1 — Keypad auto-repeat delay

The standard ER9X firmware (and the original TH9X version) do not wait a while before commencing key/button auto-repeat. Hence, if you hold a button down just a tiny bit too long, you end up going two or three ‘clicks’. This frustrated me, so I added a longer initial delay, as we’re used to having on PC keyboards etc.

Feature 2 — Better beeps and buzzes

If you have a stock Turnigy/iMax 9X you like to rave about, I’ll bet you don’t mention the hideously annoying/ear-piercing buzzer/beeper thingy!

And, if you’re planning on following my Fr-Sky telemetry additions, you’ll probably be wanting various different tones frequencies/tunes instead of the stock high-pitched squeal for every event.

My solution was to disconnect the stock ‘screamer’ and replace it with a miniature speaker — WITH A 4.7uF CAPACITOR in series. The capacitor is needed to prevent damaging your CPU and/or wasting battery power. I got my ‘speaker’ out of some old budget headphones.

To make it work, I’ve written code to implement “beeps” of any desired length and at lots of different frequencies. So, I can now have long, high pitched tones or short, low pitched tones — or even complete tunes like, ‘Knees up mother brown!’, if I want . :-D

All this will come in handy when I have my AoA (Angle of Attack) sensor and telemetry feedback for ‘always perfect’ landings … or at least, such is the goal. I plan to use tones similar to the rise/sink sounder in modern gliders, and probably a plug-in earphone.

The version I’m posting today has all present tones the same frequency (lower!) and at the same durations as the original ER9X firmware. It  works so well that I’ve actually turned ‘key beeps’ back on. Much more pleasant to the ear now. :-D

The Code

[This code is based on ER9X trunk, release 262]

Pre-compiled HEX

The file er9x-hex-gruvin-20101111.zip contains four pre-build hex files ready for flashing. Their names include the features they contain. The names are …

er9x-frsky-rptdelay-speaker.hex
er9x-frsky-rptdelay.hex
er9x-std-rptdelay.hex
er9x-std-rptdelay-speaker.hex

NOTE: The two FRSKY versions require that you re-wire stuff inside your 9X. “std” means “standard” or “not Fr-Sky”.

If you have a stock ’9X and you just want the better keypad auto-repeat delay, use er9x-std-rptdelay.hex.

Source Code

My complete source code for this version can be found in the following file: src-gruvin-20101111.zip

There are two new make directives for turning on and off the new features. They are:

BEEPER -- values can be BUZZER (the default) or SPEAKER
KEYRPT -- values can be STD (the default) or DELAY

Example make usage to include both features, as well as Fr-Sky support …

make EXT=FRSKY BEEPER=SPEAKER KEYRPT=DELAY

The Future

As time goes on, I may end up as a submitter for the ER9X project itself. However, if I start adding lots of custom features, I’ll probably fork off with my own project – Groovy9X I suppose :-P . Time will tell.

Speaker / Capacitor Installation

Correction to the above — you can’t actually simply “replace” the stock beeper with a speaker. The image below shows what I actually did. (The capacitor is installed the wrong way around too by the way. Negative should ideally go toward the white speaker wire.)

click for full-size

2010
11/11
CATEGORY
ER9x-gruvin
Tech
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ER9X and FrSky using Mac OS X

So I’ve joined the craze. I now have a Eurgle/FlySky/Imax/Turnigy 9X “cheapo Chinese” RC transmitter, which has been (massively) upgraded with ER9X firmware (based on the great foundational work of TH9X) and added to that an awesomely  reliable yet very well priced Free-Sky ACCST (FHSS) 2.4GHz radio module — WITH TELEMETRY.

This post was intended to be my own online notes of the firmware compile/installation procedures etc for Mac OS X. But I’ve fleshed it out some, so hopefully others will find it useful too.

There’s a TONNE of other discussion on this topic at the RC Groups official ER9X thread if you care to wade through it. Oh and the very first post there has a bunch of useful links. Well worth a look.

Click here for the full article … wherein you’ll find the programming hardware and software you’ll need, how to wire up your ’9X for re-flashing (programming) and more.

2010
11/09
CATEGORY
Tech
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PHP Web Hosting Explained

What is PHP?

PHP is short for ‘PHP Hypertext Preprocessor’ (an intentionally self-referencing looped term). PHP is a very widely used, server-side web programming language, designed from the ground up as a free platform for developing efficient dynamic web pages.

Advantages of PHP

PHP gained massive popularity over its first decade due in part because it was made available for free but mostly because of the many features and benefits PHP scripting language provided.

PHP is open source and therefore free to use under the terms of its license, including both personal and commercial use. Because PHP is an open source language, there is a huge community available for online assistance and learning. The large PHP community working on and contributing to the PHP project makes for a very secure and trustworthy application over all. PHP’s ever growing popularity ensures this trend will continue for years to come.

PHP is very easy to use and runs fast. Even a brand new or currently inexperienced web developer can learn the basics of PHP development in a very short period of time. PHP is very simple. HTML coders can integrate PHP programming straight into their existing pages. Also, if you are an experienced programmer, you can utilize some of the more advanced features of PHP to create powerful Web 2.0 websites.

MySQL

Arguably the greatest advantage of PHP is its ability to interact with MySQL databases. MySQL is used by popular web applications like, WordPress, osCommerce and PHP-BB, to name just a few. PHP is ideal for interfacing with MySQL. MySQL is used with PHP as server-side tool, thus PHP and MySQL make a fantastic team for webmasters wishing to automate their dynamic web sites.

What is PHP Web Hosting?

As the name suggests, PHP Web Hosting refers to a type of web hosting service that provides support for the PHP programming language. Make sure your web hosting company offers full PHP and MySQL support at a minimum of version 5 for both.

The best web hosting companies offer PHP hosting services as there is a lot of demand for the technology. When registering a hosting service, it is necessary to en sure that you will be provided with the latest version of the PHP and MySQL. Newer versions regularly appear and each time a new version comes, you want to be using a host that is keeping up with the play. Keeping u with the latest stable version of PHP is also important for ensuring you have the most secure systems available to you.

Affordable PHP Web Hosting

If you search the various options online, you will find that PHP hosting is in general much more affordable compared to other web hosting solutions. This is mainly PHP is an open source language and it therefore itself free. And it usually comes along with the popular database, MySQL, which is also free. The provider need only ensure the configuration of the software complies with state-of-the-art security methods.

What is cPanel?

cPanel is arguably the most heavily used and widely implemented all-in-one, high security PHP/MySQL supporting system available on the net today. When configured correctly, cPanel ensures that all system software, including PHP and MySQL and all supporting environments are maintained at the very latest, stable and secure versions. The cPanel goes further to provide extensive state-of-the art firewall and HTTP URL anti-hacker filtering to prevent attacks such as MySQL injection so that even poorly written PHP/MySQL websites receive relatively good security right at the front door. Whilst not recommended as a complete solution, these additional protections are indispensable for website developers who are more focussed on design than the detailed ins and outs of tight code security.

If you want your website to be safely protected, demand cPanel and ensure your provider keeps their system regularly updated at the latest, stable versions of all system software.

Ideal PHP Web Hosting

When you are looking for a host for your website, you need to know three basic things:

First, ensure the service has enough bandwidth to meet your website requirement.

Second, there should be enough disk space available for not just your current needs, but also your future development. Most providers allow you to start small and grow as your needs expand.

And third, the hosting package should provide you with sufficient databases for your web site requirements. Most sites require only one database, but if you intend running several different applications on your domain, you may need more.

NZ Hosting is a leading New Zealand web hosting company, who offers REAL 24/7 support via email and live-chat for client’s satisfaction. We never overload our server. All of our plans include the latest industry features available on the market. We cater for the personal blog as well as the multiple websites for large business group. Our packages are equipped with the features needed to meet all of your requirements.

2010
05/21
CATEGORY
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