the USB bootloader mode of PN7462 under Windows works very well.
The disk labelled PN7462_AU appears and I can replace firmware both Flash and EEPROM.
But I cannot mount the disk under Linux (Ubuntu 18.04 and Raspberry Pi 3).
The solution is here PN7462 updating EEPROM on linux
The EEPROM occupies seven sectors from 3rd to 9th (3.5 kB)
The flash occupies 316 sectors from 10 to 325 inclusive (158 kB)
Retrieving data ...