Recently, I was debugging an OLED display, and I just couldn’t get it to communicate correctly, which was very frustrating. So, I casually searched on eBay for a logic analyzer, planning to buy a cheap one to use. The most common item on eBay was this one:
8 channels, 24MHz maximum sampling rate, priced around 10 euros. Based on my experience with eBay, this thing was definitely Made in China, so I searched on Taobao, and sure enough:
On Taobao, this type of logic analyzer is generally priced around 30 yuan. Although it’s twice as expensive on eBay, it’s still considered cheap. So why are these types of logic analyzers so prevalent?
The description of this logic analyzer on Taobao can provide some clues 
. Yes, SALEAE, USBEE AX. Both companies have launched similar logic analyzers and PC software, which are definitely not free and cannot be solved with just 30 yuan or 10 euros. Below are the products released by these two companies:
Due to the simple hardware circuits and readily available pirated software, these two logic analyzers have been widely cloned 
Anyway, I quickly bought one on eBay.
Upon opening the package, I wondered if the seller really didn’t need to localize it? At least they could have made it international!
It shows a cheap quality feel, which is exactly what I wanted.
Gently prying open the shell, let’s take a look at the circuit board.
The wiring is a bit random, and a few chips hold the scene together.
Besides capacitors and resistors, here are some of the components:
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Cypress CY7C68013A-128AXC
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NXP 74HC245
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EEPROM 24C02
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LDO AMS1117-3.3
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24MHz Crystal Oscillator
The most expensive component here is Cypress’s FX2LP series chip CY7C68013A-128AXC, which has the following prices among stock distributors:
Even at the futures price, this logic analyzer should have no profit 
. I don’t quite understand.
However, this is not a bad thing for us poor hobbyists.
I connected this logic analyzer to a computer running WIN10.
We can see that it has stolen the ID 0925h/3881h, which is the USB device description of Saleae Logic, allowing it to be recognized by PC software as a Saleae logic analyzer. The seller on Taobao will provide a download link for the pirated software.
However, open-source enthusiasts can also try this software from sigrok, PulseView, which provides open-source firmware fx2lafw specifically for this type of logic analyzer based on the FX2LP chip.
On Windows, you need to use the built-in software Zadig from PulseView to install the WinUSB driver for this type of logic analyzer, while on Ubuntu, the driver is automatically installed when installing sigrok.
PulseView supports a range of common Protocol Decoders, such as SPI, I2C, UART, etc.
Although the cloned logic analyzers cannot guarantee hardware performance, they should still be able to operate stably at lower signal frequencies, such as <1MHz, which is more than enough for general hobby projects.
In summary, a 10 euro/30 yuan cloned logic analyzer + open-source fx2lafw + open-source PulseView can be considered a blessing for hobbyists 
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