Google translated into English.
FTDI driver (version 20814) upon detection of counterfeit chips FT232RL writes to the internal EEPROM at the address 0x002 zeros (PID devices), and at 0x03e writes a code to the CRC converged (located on 0x03f address). On the original chip, these operations came to nothing lead, because he has the EEPROM 32-bit organization. When writing the word with an even address comes only the buffering, while recording on an odd word address is written to just two words. Fake chip is recording every word, so he spoiled PID (becomes 0x0000). Therefore, the fake chip at the first connection is normal is determined (until the data in the EEPROM is true), and after the reconnection ceases to be determined. The idea is that the driver will spoil the original and previous generation FT232BM chips with external EEPROM, which has a 16-bit organization. To see the damaged chip again, you need to install a slightly modified driver. The inf files are added to the line PID_0000, then he would support both original and "spoiled" fake chips. But only up to the driver update. Promptly distinguish ******* from counterfeit chips, you can use a utility that tries to write the data EEPROM at an even address. If it succeeds - the fake chip. Then, the utility restores the previous value. In addition, the utility allows you to restore the PID (in the original chip he is equal to 0x6001) without violating the CRC. Recovery is possible only with the modified driver set. Another difference - in the original chip consumption current of about 9 mA, while the fakes about 35 mA.
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