if it is working, you do not need to upgrade the firmware.
- Load firmware flasher
- Eject SD card
- Check you have ejected the SD card
- Did I mention ejecting the SD card?
- Run the firmware flasher
- Update the BIN and SYS files on the SD card
- Reinsert the SD card and reboot
Tapuino or TZXduino or via a phone app. Also in that folder, there is a wav file. You can play that into the Spectrum using a audio player on a laptop or phone.
SD2USB card reader, but you can use something else if you must.
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