Ahead of our visit to Maker Faire Shenzhen 2015 later this month, we've had our mind on the amazing array of electronic components that you can get in China - and we're not alone. China in general, and Shenzhen specifically, is generally regarded as the heart of the electronics industry, providing everything from completed devices ready for resale through to individual components other manufacturers have long since stopped supporting. Opportunities for bargains are always present, but so too is the risk of being ripped off: back in 2010, our friends at SparkFun famously received chips with no active components at all, simply lumps of copper with fake encapsulation. Even when a chip appears to be working as it should, there's no guarantee that they're in-spec - especially when it comes to low-cost clones which mimic the functionality of popular chips like the Atmel ATmega family of microcontrollers. That's where you need to get a bit clever, reverse-engineering the devices and testing their limits to see if they are truly drop-in replacements for the more expensive originals or hacked-around simulations that won't hold up to real-world use. Andy Brown has recently been doing exactly that, investigating cheap ATmega8 chips from AliExpress which cost less than $1 (65p) each in lots of five - including delivery. Using a series of C programs, Andy was able to probe various portions of the hardware - the internal oscillator, external crystal support, GPIO Port D, memory, and the timer0 peripheral - and prove that they operated as they should. While more reverse-engineering work would be required before signing off on the part as fully compatible - and, for preference, finding original sources for the parts before the almost-certainly-fake Atmel labelling is applied - Andy's work is a good demonstration of how to make sure your China-sourced 'bargain' is at least close to what it claims to be.
ATmega8’s were available from sellers on Ali Express at the ridiculously cheap price of five for US$4.95. Less than a dollar each including shipping. I just couldn't resist it so I bought a pack and about two weeks later they arrived. Would they work? I don’t know.