There have been many project to create a storage interface for ZX spectrum like SMART card, DivMMC, ZXMMC, DivIDE . .. .. ..

This version will firstly focus on make an DIY version for SD/MMC card that give you the ability to play all you spectrum game selected from a menu.

The design is simple an is the first or a series SD/MMC interfaces for other hardware platforms. Plans are for ZX81, Dragon 32, Oric, MSX.

This version will use a standard Kempston joystick interface, a Boot/menu ROM and the SD/MMC interface.
Target price for a complete system is less 150Nkr or €17. Depending on if it will be external or internal.

When ready, I hope to add this to the Harlequin project.

Principle is as following.

1.Boot from external 16KB ROM.
2.Read menu for SD card as present to user with choose to select program or jump to native machine.
3. Load file to memory from SD card
4. Create switch routine in ram and switch to program

Other features:
Kempston joystick interface
Reset button
Enable/disable boot ROM

You will find the layout as is processes here.
Version 2 is available, simplified without address decoding

Hope to find some volunteers to help with the code.

Sources for information:
http://piters.tripod.com/portadr.htm
http://elm-chan.org/docs/mmc/mmc_e.html
http://elm-chan.org/fsw/ff/00index_p.html
http://8bit.yarek.pl/hardware/zx.joystick/

Del dette:
  1. Hi again

    Not too easy for home made pcb but not imposible. Additional work will be need to separate some closed tracks.
    It could helps small change in some tracks, they are too closed.

    Still following this Project. 😉

    Regards

  2. Hi,
    I just got the prototype board this week.
    Have started to write test code for the card. Så fare only 2 mistakes.
    Needed to insert a diode from the flip flop to ROMCS. Could not force ROMCS low only force hi.

    Kjell S.

    • Hi,

      If you want I can send you the current PCB free of charge.
      🙂
      The PCB and schematic are not updatet yet.
      Will add some pictures of the prototype board.

      Kjell S.

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