Ikea's record breaking shelves

Oh dear, after several years the Ikea Lack shelves have finally given up.....

Doctor Who - Pop Up

This is an old post, preserved for reference.

The products and services mentioned within are no longer available.

I've been a fan of Doctor Who since before most of the current cast were born. So I was it was quite an honour for me when, a couple of years ago, a short story I had written was recorded by Big Finish Productions. They produce and excellent series of 'dramatic readings' and full cast audio adventures of classic Doctor Who, using many of the surviving cast.

My story was called 'Pop Up', and featured the third Doctor and Jo Grant. It was performed by Katy Manning (who played Jo Grant in the TV series in the early 70's), and features on the 3rd volume of their 'Short Trips' series.

This week it is on special offer: 

2022 Note: The CD is out of print, but the download is still available:

Short Trips Volume 3

SATA Docking Stations Review

This is an old post, preserved for reference.

The products and services mentioned within are no longer available.

I frequently need to be plugging various hard drives into test machines, to wipe drives, to perform external disk tests and virus scans, and for data recovery. So one thing I used a lot is an external SATA dock. For the last couple of years, I've been using a pair of Akasa Duo Docks (AK-IC008-BK). I've found these very solidly built and useful. These sit on the desk and plug into the PC via an eSATA port, although there is also a USB 2.0 port. There is a slot on the top to insert 1 3.5" desktop or 2.5" laptop hard drive or SSD (but not at the same time as they share the connector). Then thanks to SATA AHCI hotplug, these appear as additional drives to the PC. Where they can be wiped, scanned etc.

These, along side the IDE version I built a while ago, have served me well. But with SSD's becoming cheaper and therefore more prevalent, I've noticed I'm not getting full speed out of them. Further investigation has shown that the USB 2.0 port is the problem. Whilst on some external drives, there is a switch to choose between eSATA and USB, this uses a chip, and that chip seems to be limited to SATA 1. So even with the a SATA 2 or 3 drive and a SATA 3 capable motherboard, I'm seeing speeds limited to around 150MB/S rather than the 500MB/S some of the SSDs are capable of if directly connected to the same motherboard. I've had a look inside, and there doesn't look to be an easy way to bypass the USB (which I don't use), without cutting the tracks and trying to bodge what are meant to be balanced impedance tracks. So time for an alternative.

The first I looked at was a Zalman ZM-MH200 U3 Dual USB3 HDD Docking Station. Both drives in the same unit, so a saving on bench space. This turned out to be a disappointment in a number of respects. Firstly before I'd even plugged it in it came with a US figure of 8 mains lead and two, yes, two, UK mains adapter plugs - neither of which was fused. I may be wrong, but I thought it was illegal not to have a fuse in the plug?

Luckily I had a box of figure of 8 leads with fused, moulded UK plugs on the end, so I used one of those. This thing supports two separate drives at a time, of either size, so was going to save me bench space. However, I assumed / hoped / expected that these would appear as two separate drives, but it doesn't seem to work like that. It goes through some 'intelligent' RAID chip which allows you to combine the two disks into a single drive with either RAID 0, RAID 1 or JBOD. Quite why you would want to do this with interchangeable removable drives, and not a fixed pair of drives inside the PC or in an external enclosure is beyond me. Possibly to be able to replace a disk if one fails (but how do you tell without a manager?) and with only 2 disks, a RAID 0 or JBOD array would be lost. However, that is how it works, and it doesn't allow the two drives to be accessed separately. There is a 'DUAL' switch, but I haven't been able to get it to reliable reliably recognise the second drive, the activity light doesn't appear and there is some confusion about which is which. Oh, and finally, this is probably a limitation of the USB hard drive support in the Windows, but it doesn't appear at all if there are no partitions on the disk, so is useless for new drives or data recovery. Time for plan B (anyone want a Zalman Dual Dock?).

Plan B turned out to be an internal version, the StarTech SATADOCK525. So even more bench space saved. This uses a single 5.25" optical drive bay to provide 2 SATA drive slots. One for a 2.5" drive, and one for either a 2.5" or 3.5" drive. Both of which have separate switchable power and activity LEDs. These connected directly to the SATA ports on the motherboard, so no issues with intermediate chips reducing speeds or confusing things. These are pretty much exactly what I was looking for. The construction isn't fantastic, the door flaps are a little flimsy, but are easily removable if they get worse. The other issue I had is the LEDs are dual purpose, they are bright blue for power and red for activity, but the activity signal is provided by the drive and so some drives you can see a sort of purple when there is disk activity, but for most it just get washed out by the bright blue. So at some point I expect to be removing the door flaps and buffering the activity LED's.

The power to the drives is separate, I can sort of see why, but I would have preferred a single molex power connector for both drives. I decided to add two docks to give me most flexibility, 2x 3.5" drives or up to 4x 2.5" drives, so I had 4 sata power connectors to feed. In the box they provided 2 single molex to sata adapaters, these would have been better if they had been a single molex to dual sata. I ended up making a custom cable using the push down style connectors salvaged from dead power supplies to give quite a neat finish from a single molex.

As you can see in the picture, the SATA data connectors are the type which don't latch, and since the unts were so short, the plugs easily fell out. A large dollop of hot melt glue firmly fixed those in place. And finally, all the drive bays installed in the Corsair 600T case of my test machine.

Online Learning

This is an old post, preserved for reference.

The products and services mentioned within are no longer available.

I have recently taken part in quite an interesting experiment. MIT (or rather MITx 'an online learning initiative of Massachusetts Institute of Technology') have placed a module from one of their electronics degrees online, course 6.002x (Circuits and Electronics). So, for the last 14 weeks, I've been watching lectures on youtube and completing online exercises, homeworks and exams.

A key element of the technology they used is that the work was automatically marked when you clicked the 'Mark' button, so you get immediate feedback with a tick or a cross. It is very rewarding to sit down, work through something, hit mark and see a load of green ticks. But equally, it is disheartening when they're all red, and of course, you don't get any marks for working. However, you can go back and try to work it through again, and in the exercises, you can click to show the correct answers. They also published worked versions of the questions the following week.

I'm pleased to say that I passed the course in the end, so this has been a useful refresher of elements of my degree in microelectronics from the Newcastle University, but also a very interesting experiment in online learning. I look forward to the next course being announced.

Further information at http://www.mitx.mit.edu/

Update: Some statistics from MITx: 6.002x had 154,763 registrants. Of these, 69,221 people looked at the first problem set, and 26,349 earned at least one point on it. 13,569 people looked at the midterm while it was still open, 10,547 people got at least one point on the midterm, and 9,318 people got a passing score on the midterm. 10,262 people looked at the final exam while it was still open, 8,240 people got at least one point on the final exam, and 5,800 people got a passing score on the final exam. Finally, after completing 14 weeks of study, 7,157 people have earned the first certificate awarded by MITx, proving that they successfully completed 6.002x.

Asrock CIR Remote Demystified

This is an old post, preserved for reference.

The products and services mentioned within are no longer available.

A number of Asrock boards come with a 4 pin header labelled 'CIR'. The manual includes diagrams showing how to connect a special receiver using a front panel USB connector, but most boards do not come with the receiver or remote.

Since the device looked more than just an IR receiver, I had left those alone in the past, expecting they required that particular device to work correctly. However, I have recently purchased an Asrock Z68M-ITX/HT board which does come with a receiver.

At first glance this looks like a USB device, and indeed it does use a USB connector and plug into a front USB socket. But you are meant to move half of the front panel USB 10 pin connector so it takes in the CIR header and 1 of the USB ports.

Installing it doesn't show anything on lsusb on linux, and there is no new device detected under Windows  because it isn't USB. Inside are two standard 3 pin IR receivers, another sideways one and two SOT23 chips.

The two chips turn out to be AND gates, so it makes a quite neat little circuit, three active high IR receivers whose outputs are ANDed together to make a single active high IR signal. This is fed through to a Nuvoton W836x7HG CIR receiver, which is supported out of the box by LIRC in recent kernels (certainly works on my Mythbuntu 11.10 boxes). It is supported by the 'Acer Aspire 6530G_MCE' driver. I haven't gone through a full keymapping as yet, but most of the keys map to the Acer ones.

One very useful part of this is BIOS support of power on by CIR, so with the adapter in place and the BIOS option 'Power On By CIR' enabled, you can switch on the PC using the remote. Nice.

As good as it is, my main issue is that it isn't really convenient to have it hanging out of the front USB port.

So I thought I'd see how it worked wired direct to a standard TSOP4838 receiver. I wired one up using an old CDROM audio cable, with the ends de-pinned and rearranged appropriately.

This worked fine under test, but the receiver wasn't particularly solidly held in the socket so I soldered the device onto the cable.

I then glued it to a suitable gap behind the mesh on the front of the case.

The 4 pin connector goes on the CIR connector wired as follows:
1 - 5V (this should be at the same end as the red wires on the USB connector)
2 - IR RX (this is the active high output from the IR receiver)
3 - IR TX (this is not connected, but I presume this is for an IR transmitter?)
4 - 0V (this should be at the same end as the black wires on the USB connector)

Windows 8 Review

This is an old post, preserved for reference.

The products and services mentioned within are no longer available.

I've been running the Windows 8 Consumer Preview for a while now, so here are some of my thoughts on it.  Let me say at this point, I'm not the average user, so this is just my take on things, on how I want to use it.

Firstly, it works - it does the job. I'm writing this in Windows 8 and it is perfectly usable in that sense.

There are a few things that are going to take a bit of getting used to though. Metro is the most obvious difference, as a replacement for the good old 'Start' button (not that it has actually said 'Start' on it since XP). And this is where I think it falls down. It is trying to be all things to all people, both a desktop and a tablet operating systems and they do seem to jar at each other. There's basically two interfaces, the new one, Metro, with all it's touch friendly large coloured boxes and the other which is pretty much Windows 7 without the start button.

They seem to coexist, but don't exactly cooperate. I run multiple screens as I find this very useful, particularly in applications which support this way of working and allow you to have toolbars on one screen, the main work on another, status windows on a third etc. I have a motley collection of 5 mismatched monitors at the moment, including one portrait which is great for work processing as you can work on a whole page at a time, the right way up. Windows 8 continues to support this in it's standard desktop mode fine, but it becomes pointless when running anything in Metro. I tend to leave on monitor showing my email, and other web applications, so I can always see their status. I have another small monitor which normally shows my music player, has the taskbar, and the desktop gadgets like the clock and calendar. When I start a Metro app, all of these close and just show the wallpaper. This is a bit pointless as I'd rather it kept displaying the apps that were running. Admittedly, to the average user with one screen this wouldn't be an issue.

My second main gripe is why didn't they just leave the start button there? Fine you can go into Metro and use any new apps designed for that environment, but for everything else, you have to hover and bring up the right hand menu and search for it (a bit like the Ubuntu Unity launcher), (or use Windows + F if you remember your keyboard shortcuts). I then pin it to the task bar (as I used to do in Windows 7 anyway) as this is quite a convenient way to start apps, particularly those which support the droplists of recent files.

One of the first things you get after installing Windows 7 and earlier is a warning about installing so anti-virus software. There isn't one, and it's not obvious what is happening about anti-virus protection. After a bit of diffing, it seems that have integrated Microsoft Security Essentials into the OS under name of Windows Defender, but there isn't an obvious way to start it and gone is the reassuring green ticked house in the taskbar that allows you to track its status. I wonder what it does if there is a problem? Making it a standard part of the OS is a good move. I tend to install Microsoft Security Essentials by default on all new builds, refurbished PCs and reinstalls as it seems to do the job and is less intrusive that other free solutions like AVG (mainly I suspect because AVG need to try to sell you the full version, whereas Microsoft have already sold you Windows so have nothing to tout).

Like Apple and Google, they like users to login with their Microsoft ID, a Live mail account normally, although it is possible to set it up to use a standard local login rather than an email based one. Many of the Metro apps seem to need it. There is a new music player, but that only works if you have an XBox Live account. I don't have an XBox, why do I need an XBox Live account to play a collection of local MP3 files?

Media player is also installed for the desktop version, and as a side note, does not appear to have the same annoyance that it will stop playing an MP3 playlist if you insert a CD (to install software for example), even with autoplay etc. disabled as it does on earlier operating systems.

Duality again in web browsers. IE 10 is there in Metro, IE  9 in the normal desktop, and as usual if you have something open in Metro, all the other windows disappear.

It seems Microsoft have taken the multitasking operating system and returned it to the days of single tasking. It reminds me of how I used to run Windows 3.11. I booted up to a full screen DOS menu, all bright colours and squares, not a curve in sight. I could then select from a number of full screen, single tasking applications like Protext and Quick Basic etc. but also had the option of running Windows if I wanted (and that didn't have a start button either). But I could only run one full screen application at a time, and had to leave windows if I wanted to run anything else. There was nothing wrong with that way of working, I happily used it for many years before Windows 95 and so on came along and offered multitasking and start button and all. They got it right again in 98SE, went a bit wobbly with Windows ME, then got it right again with XP. Wrong again with Vista and then Windows 7 seemed to be a nice place to work again. Has Windows 8 fallen into the 'every other operating system is rubbish' pattern I wonder?

So all in all, will I be going back to Windows 7 after my brief sojourn with Windows 8? Yes, I think so.

Will I be reconsidering this when it is finally released? Of course, but still with a due sense of precaution and dread. I'd be surprised it they didn't ship a 'Business', 'Professional' or 'Desktop' edition with a start button.

2022 Note: I think that was a fair appraisal of Windows 8 as it was when it was released. I did indeed go back with 7 and kept going back to 7 and later to 10 when I needed to do Windows development. Most of the rest of the time has been various favours of Linux,. My Linux is currently Mint flavoured.

Atari 800XL Memory Repair

This is an old post, preserved for reference.

The products and services mentioned within are no longer available.

I was tidying up and came across a bag of 30 pin SIMMs. Definite relics of the past, some were 256K and you needed 4 of these to get 1MB memory, enough to comfortably run Windows 3.11. I can't really see anyone coming to me with a computer for which these would be an upgrade. The rest were 1MB sticks, and with 4 of those, your 4MB was just enough to scrape your way into Windows 95. I'm a hoarder at heart, so I couldn't possibly throw them out, but I was wondering how I could justify keeping them, what possible use could they be?

Then I remembered I'd found a use for one back in the 1990s when I didn't have access to replacement DRAM chips. My dear old Atari 800XL, the first computer I had with sound and colour (or color as having to repeatedly type COLOR and SETCOLOR didn't help my spelling back in the day). After a long, hard life, it had become a bit flaky. A unique feature of those Atari's was a built in self test, you could test the sound, the keyboard the ROM and the RAM. The RAM test should show up 48 green squares (1 for each KB of memory), but I was getting about a dozen RED ones scattered around.

This is where the 30 pin SIMM came in. I basically stuck it on top of the existing chips, and wired it in place. This was a while ago, so I don't have the wiring diagram to hand, but from what I remember the address and data rows / columns were all driven through resistors, so all I had to do was cut the end of the resistor where it went to drive the old chips and wire it to the nearest appropriate pin on the SIMM - although ideally D0 goes to D0, D1-D1, D2-D2 etc. with RAM it doesn't really matter if D0 goes to D3, D1-D6 and D2-D2 etc. as it will only be reading back what it wrote, so it will be in the correct order. The 1MB SIMM I had used was overkill in terms of capacity, I just tied the spare address lines to ground - at some point in the future, I never got around to looking at memory banking to make use of the extra capacity. The timing was also a bit more than high enough, the originals looked to be 150nS, the replacement were 70nS, so more than fast enough.

Not the neatest job in the world, it was sort of proof of principle, I was interested to see if it could work. No problems at all, memory test came up with 48 green dots and ran for a couple of hours with no problems reported. And most importantly, Spellbound worked!

This is now very much a spare as the keyboard and button panel are both incomplete, but it does actually run.