Archive for the ‘components’ Category

Gyros and accelerometer in Wii controller knockoffs

Wednesday, November 17th, 2010

Here’s another post in the spirit of cracking things open. This time it’s a Wii Nunchuk and the Motion Plus. Well not the Nintendo ones, but cheap Chinese knockoffs.

First up is the Nunchuk which has an Analog Devices ADXL335 (and a 2K 2-wire EEPROM), mounted on a low quality PCB:

The Motion Plus has the relatively well known InvenSense IDG-650 and ISZ-650 dual-axis gyros. The build quality is also much better compared to the Nunchuk:

A quick peak at the WiiBrew wiki learns that they are not the same components Nintendo uses in official accessories, but who cares. It’s just fun to play with sensors that don’t cost an arm and a leg ;) And they all come with datasheets (and appnotes) which can be found at the manufacturer’s website. Only downside are those pesky leadless packages.

USB SATA bridge

Saturday, November 13th, 2010

A while ago I thought about using a SSD instead of a SD card to the musicplayer. Since SATA IC’s aren’t exactly easy to obtain, I headed over to DealExtreme for a Mini USB 2.0 to SATA Dongle with the intention to rip it apart. Took a month to arrive (if you’re expecting stuff from China be prepared for a long wait… packages seem to take ages to arrive these days…) but today the day has come to go berserk (well actually the casing came apart pretty easily).

I was kind of expecting some kind of  JMicron chip, but was surprised to find a Moai MA6116 chip (and an unmarked crystal). Unfortunately no datasheet, but who knows what this thing can be used for. The manufacturers website only mentions this (for the A revision):

MOAI MA6116A is a bridge chip for USB to SATA interface, translating the host SCSI command to ATA/ATAPI command of SATA device, targeting the external HDD application. MA6116A complies with the USB Storage Class specifications ver.1.0 Bulk mode protocol and compatible with Windows 98/2000/XP/Vista/Win7, Mac OS 9, Linux Redhat. With the in-house DMA and Transceiver capability, MA6116A provides the market most outstanding read/write performance and BOM cost.

ST, what the hell!?

Thursday, November 11th, 2010

So STMicroelectronics has revamped their website. This could have been a welcome change, but instead they stuffed it with flash. And I’m sorry to say it sucks even harder than before…. How hard can it be to get a decent website running? How on earth is anyone supposed to select a product if it’s impossible to find? And who’s idea was it to put fancy animations in a product catalog? And each time you select something a new page is opened…. omg….

ST, what the hell… are you deliberately trying scare people away?

Excessive shipping costs

Monday, November 8th, 2010

Today I’ve been hunting for unusual shaped LEDs – square, cylindrical, tiny, those kind of LEDs. And the one thing I’ve learned is that EU shipping costs are ridiculous! Here in the Netherlands I haven’t found a single source. Ok there’s Farnell and Mouser but they require a minimum order of 50 or 70 euro respectively. Which is unrealistic unless I want hundreds of LEDs (well with Farnell’s pricing policy it’s more like a handful…).

Next I looked at neighboring countries. In Germany it seems DHL has taken over and they charge almost 10 euro (what ever happened to DPD?). Ok I’ve found German stores that ship for less, but they sell LEDs for insane prices. 10 LEDs for 6 euro including shipping. Gets expensive real fast if you’re looking for small amounts of different colours and sizes.

After Germany the UK got my attention. Found a store that sells all kinds of sizes, shapes, colours and good prices. Perfect for what I have in mind. So I tick 10 different LEDs,  one of each. Go to checkout and calculate shipping… 27 pounds… for 10 LEDs… WTF?!!? Nice one TNT. There’s nothing wrong with a nice padded envelope you know.

Depressed by this reality I did a search for my regular online stores in China, Thailand and the US. And guess what? Normal to no shipping costs all over the place and low component prices. So once again I can ship stuff from the other side of the world to my house at a fraction of the cost it would take to ship it from ‘around the corner’.

Just begs the question wtf is wrong with Europe?! This is not the first time and certainly not the last. And in case anyone is doubting whether or not it’s worth to shop around – yes it is! Granted sometimes the shipping costs/time outweigh the benefits. But other times you win big time. The most extreme example I’ve ever come across was when I ordered my Losmandy equatorial mount. It took a couple of evenings to get things in order, but I saved 1100 euro (all in and yes that’s a 4 figure number!), simply by ordering outside the EU.

Just do a little initial research ;)

Farnell price differences

Wednesday, September 29th, 2010

While shopping for components I noticed some (huge) price differences. Here’s an example;

Same company, just different countries. While to seems pretty much standard to rip off Europeans, these are not small differences, especially considering components are usually sold in large quantities.

Let’s say I want 50 connector; that’s £26,- (= €30,14) in the UK. In The Netherlands it totals to €79,-…. more than 2,5 times the UK price! What the hell…

Also checked a few other things, but those had more normal differences. Limited to connectors only it appears.

Dev boards

Monday, September 27th, 2010

Yee a new ‘toy’ has arrived. After waiting only 3 months to the day, a little carton box containing TI’s MSP430 Launchpad board finally found it’s way to my doorstep. It was cheap, comes with free tools and no shipping costs which is a huge pro if you just want to try a new product. No idea what to do with it yet, but I’m sure something fun can be made with it.

Also very nice are the extras. Apart from the nice box it comes in, it includes 2 controllers (2211 and the 2231 which has an USI and ADC), a 32.768 kHz crystal, headers and an USB cable. And to top it off there are 4 anti-slip pads beneath the PCB (it’s often in the small details). Kudos to TI!

Btw, this thing is actually sold below the actual cost of the parts. Just the 2 LQFP IC’s (a Serial-to-USB Converter and a 16-bit ULP MCU with 55kB Flash and 5120B RAM) are over $10 @1k units.

Speaking of dev boards, ST recently introduced a nice STM32 board. According to ST you can get one for under $10, but I haven’t seen those, not even at the distributors they link to. A more realistic value is €12,55 which boils down to $16,90 incl VAT at today’s exchange rate. Yes that’s right, 160% more than ST advertises with. Still not bad, but saying it’s under $10 is just a big lie.

Anyhow, I’m thinking of getting 1, mainly for quick testing. Right now the Futurlec board and some chips is all I’ve got, which is a bit of a pain when you quickly want to swap boards for some simple testing. Besides that I’m looking forward to giving that ST-link thing a try.

The downside is that ST throws up some barriers. You can only buy the board through big distributors, which for us Europeans means you’re screwed as a private person. These distributors won’t even talk to you unless you place a minimum order value which is way higher than the board alone. ST can learn a thing or two from TI when it comes to bringing their products to a wider audience.

Secondly the whole ST-link thing only comes with Windows software. However no surprise there given their complete lack of non-MS support previously. A bit of a downer, but no show stopper.

S/PDIF is here to stay

Sunday, September 19th, 2010

With playback working again it was time for another addition; digital out. After some soldering and enabling I2S on the decoder the setup was ready for test run. Hooked the monster up to an Onkyo receiver and voila.

First some details. Currently the VS1053B is configured to output a samplerate of 48 kHz (this is also the highest supported samplerate for all codecs). This goes directly into a CS8406 S/PDIF transmitter which is wired in hardware mode. A second option would be a 96 kHz I2S signal. Even though the decoder support 192 kHz it can only output it with MCLK divided by 2. The CS8406 only supports clock ratios down to 128 * Fs. For 192 kHz to work it must go down to 64 * Fs.

At the moment it only uses TOSLINK, but the final version will also have coaxial output. It’s just that I don’t have the required pulse transformer lying around.

Back to the receiver. It detects the output as a 44,1 kHz PCM signal. For a more isolated test I hooked up AKG K 701 headphones which is know for it reference like quality. And wow, what a thrill. This was simply the best sounding audio I’ve ever heard not coming from a real CD.

I could still hear some things I didn’t like (high tones), but at this time it’s unknown what the cause is. Could be the recording itself (need to compare with original CD), it could be samplerate conversion (48 kHz to 44,1 kHz), could be the setup (just think of how anal audiophiles can be about the smallest things ;)), etc. Just a matter of proper testing, listening and comparing.

Also one thing that’s bothering me is the interference the setup has on my cable TV signal (doesn’t affect HDMI). At the moment I’m just blaming all the breadboard wiring which probably acts like a small transmitter. The board is located almost directly below the inputs of the TV and since the cable signal already is very weak (some stations are half snow even without any other electronics close by), so it’s not directly a problem (not to mention the lack of programmes worth watching… but that’s another story ;))

Digital out soon?

Friday, August 27th, 2010

Some missing SMD adapter PCB’s arrived today. Can’t wait to give this combo a try :)

More arrivals

Friday, August 6th, 2010

Today brought more components, most importantly a couple of VS1053B chips, the STM32 stamp and some breadboards. Not all the VS1053′s will be used immediately, but since these can be a bit difficult to obtain a few spares can’t hurt.

I plan on playing with the stamp this weekend. Even though the intention is to use the Stellaris controllers, the stamp seems easier to start with. Since I have no prior experience with these kind of ARM controllers, this will be challenging enough for now (I did do some development on a GP32, but the dev environment is very different). This is also where the additional breadboards come into play. Both the stamp and the VS1053B breakout board take up 2 boards each due to their width. One runs out of free breadboards pretty fast that way.

A second Arduino pro mini also arrived for practical reasons. This way I can work on the remote without having to break up the current player setup, which is still useful for software development (just as long  you don’t play FLAC files).

Exciting days ahead!

Parts arriving

Thursday, August 5th, 2010

Components started arriving again. Normally this is nothing special, but this time I’ve got a surprise for you (and unexpectedly got one myself…). I’ve been in limbo as to which MCU to use. The AVR is missing a few much needed cycles for FLAC, while the STM32 is overkill. Browsing through Farnell’s catalog, I ran into the Stellaris LM3S800 series which looked like a good middle choice. Not much peripherals, but running at 50MHz for a price of not too much more than the ATmega328p. As good fortune would have it, they had the LM3S818 on sale. It’s almost the same as standard LM3S800, except that it has a few extra things such as 6 ADC channels, 6 PWM pins and a quadrature encoder, but at the expense of I2C and some GPIO (ADC pins can not also be used as GPIO). Let’s see where this takes us.

Unfortunately after unpacking I discovered I made a mistake while selecting components. Instead of 0805 sized capacitors 1 strip had 0402 sized ones… 500 of them… How on earth am I going to solder those… LOL, probably not. To give you an idea of how tiny these little buggers are, they almost fit between the ridges of my fingers:

And that’s not all, it seems I’m fresh out of 28-pin SOIC adapters, so even though all the digital audio out components are present, I can’t use them yet (the CS8406 transmitter is too expensive to just smack on some half baked support board (or even worse a wire web)). Patience my dear readers ;)