Semiconductor company Future Technology Devices International (FTDI), which in 2014 was caught out bricking products built using knock-off chips, has again been accused of fooling around with device drivers.

Back in October 2014, the company shipped a device driver that checked the authenticity of USB chips claiming to be FTDI. If it detected a non-original chip, the driver would stop the host operating system seeing the device by setting its USB product ID to 0.

That release led to criticism that the company was penalising people who didn't know they had an infringing product. The company backed down and stopped pushing the offending firmware as an automatic update.

That stance seems to have changed. In this weekend thread at David L Jones' electronics engineering site EEVBlog, tinkerers are complaining that the drivers are being pushed out automatically again.

Instead of bricking the target, the posters reckon what's happening now is even worse: “Sending random characters on the RS232 interface may cause really bad things to existing products and the buyer often had no chance to know that he bought a fake chip”, writes user RFZ, who first noticed strange things happening.

Not everyone is sympathetic to the issue, with many posters saying the solution is obvious: just avoid fake chips. As one noted, “These counterfeit companies are welcome to build their own devices, but they should also be writing their own drivers and going through the same process as FTDI to integrate those drivers into consumer operating systems, maintaining them, etc., in order to make their devices usable to end-users. What's that? Doing so would mean they'd have to charge FTDI-like prices? Oh shucks, I guess the world does make sense after-all.”

RTZ turned up a fix, which is included in the discussion: “If you manually select an older driver, like 2.08.30, you have to change the driver not only on the obvious "USB Serial Port (COMx)" (ftdiport.inf) but also the corresponding "USB Serial Converter" (ftdibus.inf) listed under "USB-Controller" in the device manager. After changing BOTH to 2.08.30, the chip works fine again. It is easy to see if you list the devices by connection.”

If you've spotted issues with FTDI drivers again, you know where to find us. ®