Have seen this also and wondered about it...
https://world.taobao.com/item/14541759710.htm(Update: have found a great deal more about the ch341a chip and the so clled "usb2any" device.. need to clean this article up...
The device is called "YSUMA01-341A" - It differs from the Bus Pirate in that the Bus Pirate is a much more versatile swiss army knife of a bus communication tool in a number of ways, and this device appears to be in a number of other ways, and as far as i can tell, there is little overlap.. I eventually found (one) English datasheet for the Ch341A and its quite understandable, so maybe the statement to the effect that the ch340 that I read somewhere saying it was the worst USB-UART driver out there is undeserved or based on incomplete knowlwedge.. I have a medium sized to large collection of USB-UART adapters and my CH340 adapter is better than average in terms of compatibility..
But I had never heard about the ch341A chip until a few days ago when I spotted this dongle on taobao..
So Ive ordered one, looking forward to checking it out. somehow..
Turns out there are a number of projects involving it on github, most are targeting the EEPROM functionality.. This was the first one of several that I found.
https://github.com/karlp/ch341-linuxThe manufacturer of the chip does have a site- some datasheets/drivers are on their site.
Some are not.. like as far as I could tell, the English datasheet did not get returned when I searched for "ch341a"
Datasheet in Chinese...
http://www.wch.cn/download/CH341DS1_PDF.html their site navigation is also broken in English for me.
It appears this chip is also used in cheap EEPROM programmers
https://onetransistor.blogspot.com/2017/08/ch341a-mini-programmer-schematic.htmlFrom onetransistor.blogspot.com - - this article has a lot more info on the ultra cheap ch341a EEPROM programmer..
.. and promises an update telling more about how to use other CH341A devices.. and its API: sometime in the future...
Link to an English copy of the datasheet that I found eventually.
https://hannover.ccc.de/redmine/attachments/download/213/CH341DS1.pdf Also, on Amazon in the reviews for this product I found a lonk to a 6,5 MB RAR file that appears to have the English versions of some of the below files in it, but they are not coming from the manufacturer and for all I know, could be virus impregnated.. its possible.
So here is a chunk of the one transistor article.. (below) The ch341a - if I can use it to incorporate arbitrary i2c and SPI devices into my desktop system, semi-flexibly - may be a useful chip, for me.
"The first two are the ones you need):
CH341SER.EXE - self installing archive with USB to serial driver.
CH341PAR.EXE - self installing archive with multiprotocol interface driver (this one is for the programmer mode)
CH341SER.ZIP - archive containing driver files and serial API and library (you don't need specific API for standard serial port, but it contains some special functions to get IC version etc.)
CH341PAR.ZIP - archive containing driver files for interface mode and API (header and library to access the device and use any protocol you want).
CH341PAR_LINUX.ZIP - archive containing Linux driver source code and Linux API
CH341SER_LINUX.ZIP - Linux driver source code for serial port (don't need this one, it's already included in kernels)
CH341EVT.ZIP - some source code and tools written to be used with an evaluation board (may be useful for programming software that can access this device)
CH341DS1.PDF - datasheet, in Chinese
CH341DS2.PDF - some additional info and API documentation, in Chinese
CH341DP.ZIP - contains an ISP programming tool?
CH341DPS.ZIP - probably similar to the above, but requires login to download
A regular user only needs the first two. Just double click on each of them and when the dialog appears click on Install.
The API becomes interesting due to the versatility of the chip. You can build your own software that will read/write data from/to sensors, real time clocks or any other devices that use serial communication. You can also interface parallel devices to the chip, but this will require modification of the programmer board in order to connect to pins. There is also an universal board featuring CH341A that costs about 10 USD, but gives you easier access to chip pins.
In a future post I will talk a bit more about software (how to use the included API).