SIDE/SIDE2 Soft Drivers For SpartaDOS X

The SIDE interface, designed by Sebastian Bartkowicz, provides hard disk functionality and much more for 8-bit Atari computers, all packaged in a compact cartridge design. The device features on-board SpartaDOS X disk operating system, a real-time clock, Compact Flash card slot, programmable button, selectable “SIDE Loader”and SpartaDOS X modes of operation, and¬†512KB of flash ROM (half occupied by SDX, and half by an emulated “piggyback”¬†cartridge).

SIDE 2 – produced by Lotharek – builds on the original SIDE concept by adding CF card hot-swap functionality and enhanced ROM banking capabilities.

Using the special SIDE and SIDE2 builds of SpartaDOS X, one can enjoy most of the benefits of a hard disk interface on the Atari by simply plugging in the cartridge and turning on the machine. The SIDE driver for SDX is loaded directly from SDX’s “CAR” (Cartridge) device, and installs much of its code into the extended RAM when SpartaDOS X is using BANKED memory. And even when residing wholly in conventional memory on a stock 64KB Atari, the SIDE driver now raises MEMLO by less than 2,500 bytes.

In addition to the SIDE driver, all necessary partitioning and maintenance tools are also present on the CAR: device. These include:

  • FDISK (disk partitioning tool)
  • LSDEV (device information tool)
  • LSDSK (partition information tool)

The SIDE driver for SpartaDOS X uses the APT (Atari Partition Table) scheme, devised by Konrad Kokoszkiewicz. This ensures storage media can be easily shared with any hard disk controller which supports APT. Currently, this includes MyIDE and MyIDE II (using APT drivers), IDEa (using APT PBI BIOS), Ultimate 1MB PBI BIOS, Incognito, and IDE Plus 2.0.


Thanks to AtatiAge member ebiguy, patched versions of four OSS Cartridges (Action!, MAC/65, BASIC XL and BASIC XE) are included in the firmware package. The ROMs reside in the same ‘external’ cartridge area as the SIDE Loader, and a tool is provided which allows the user to select which of the five ROMs (the loader or any of the four OSS carts) is active. The patched OSS carts work with stand-alone SIDE/SIDE2 cartridges and with Ultimate 1MB machines (the only requirement being that one disables the ATR Swap button and enables ‘SIDE Cart ROM’ in the U1MB BIOS settings when the PBI HDD is enabled).


The SIDE/SIDE2 ROM package includes the SIDE Loader and an SDX ROM with SIDE.SYS pre-installed on the CAR: device. One may optionally update the entire cartridge ROM with a complete 512K flash image.

SIDE Loader 4.0 and SDX 4.49e (7 July 2021)

Older Versions

Be sure to download the APT Toolkit as well:


Special thanks to Candle, ProWizard, Larry White, Kyle Dain, KMK, Trub, Hias, Electron and Phaeron.

Tutorial Videos