RS92-SGP: Interfacing the EEPROM to a 5V microcontoller

I've started to experiment with the RS92-SGP radiosonde that I recovered some days ago. The radiosonde has a M95256-W 32KB SPI EEPROM where all the code and settings are stored, since the onboard CPU/DSP doesn't have any flash memory. Several parts of the firmware, including some of the settings have being reverse engineered. Thus, it is useful to interface the EEPROM to a microcontroller to rewrite some settings, perhaps to change the transmit frequency or the radiosonde's ID (the serial number which is also printed on the radisonde's box).

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