Reprogrammable 4 Megabit SMS cartridge circuit

For making dedicated cartridge versions of your homebrew games!

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

Description

This reprogrammable SMS cartridge circuit, perfect for easily making physical versions of your homebrew games! Can be installed in standard SMS cartridge shells.

Specifications:
  • 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]
  • Fits in standard SMS cartridge shells
  • Tested and pre-programmed with the homebrew game DONKEY.SMS
    (for demonstration purposes)

This design has no battery-backed RAM on-board, but with the right programming techniques, scores and progress can be saved directly on flash. The pre-programmed game, DONKEY.SMS, does that!

If you do not have an empty cartridge shell to fit this PCB, see also our reprogrammable cartridge.
[1] We can develop a custom mapper if necessary for your game or project.
[2] PFR Detect by Eric R. Quinn: https://www.smspower.org/Homebrew/PFRDetect-SMS

Ordering

Buy here

In stock : Ships within 5 business days unless noted otherwise (out of stock, pre-order, holidays, etc).
For the new year holidays, orders placed from December 19 (2025) to January 8 (2026) will only be shipped after January 9.

Item #PCB-4MBIT-SMS
DescriptionReprogrammable 4 Megabit SMS cartridge circuit
Price
1$23.99 Each
2+$19.19 Each (20% OFF)
Country of originChina

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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Keywords

Kits
SMS
homebrew
cartpcb