Reprogrammable 4 Megabit SMS cartridge

For making dedicated cartridge versions of your homebrew games!

  •  This product
  •  Circuit board (front)
  •  Circuit board (back)
  •  Programming a cartridge (programmer sold separately)
  •  Example use for homebrew
  •  Testing the mapper with PFR Detect<sup>[2]</sup>


This is a reprogrammable cartridge, perfect for easily making semi-permanent versions of your homebrew games! Built using our 4 Megabit SMS cartridge PCB. The sticker "4 Megabit Cartridge" is included but is not pre-installed, leaving you the choice to make and install your own.

  • Re-writeable 4Megabit (512 kB) flash chip
  • Compatible with PAL and NTSC systems
  • Compatible with the power base converter (or equivalents)
  • Sega-style mapper (slots 0, 1 and 2)[1]
  • Tested and pre-programmed with the homebrew game DONKEY.SMS
    (for demonstration purposes)

Does not contain battery-backed RAM, but with the right programming techniques, scores and progress can be saved directly on flash. The pre-programmed game, DONKEY.SMS, does that!

The cartridge shell we use were in fact designed for SD Card flash cartridges and have a small slot on the top which serves no purpose. If you'd rather use your own cartridge shells (from a donor game or otherwise) see also our cartridge PCBs.
[1] We can develop a custom mapper if necessary for your game or project.
[2] PFR Detect by Eric R. Quinn:


Buy here

In stock : Ships within 5 business days unless noted otherwise (out of stock, pre-order, holidays, etc).
DescriptionReprogrammable 4 Megabit SMS cartridge
1$31.99 Each
2...9$28.79 Each (10% OFF)
10+$25.59 Each (20% OFF)

We normally ship within 5 days (excluding week-ends and holidays) after payment.
Prices are in US dollars and are subject to change without notice.

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