As an alternative to your project, you can use The Mégarom T.2, it's a MEMO7 Cartridge for Thomson T9000, TO7, TO7/70, TO8, TO8D, TO9, TO9+. It contains 70 softwares. Another way is to use the SDDRIVE that is connected to the extension port of the TO7/70. It uses an SD card to emulate a floppy disk drive.

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