Ultimate / Incognito ROM editor and flasher

With the arrival of Ultimate 1MB for the XL/XE series and Incognito for the Atari 800, it had been necessary to flash complete, pre-assembled 512KB ROM images to both devices. This meant that the entire flash ROM had to be erased and reprogrammed even if only a few kilobytes of data required alteration. While various proprietary tools had been written to facilitate development, none were convenient or robust enough for regular use. Since I urgently required such a tool, I sat down and wrote the first version of UFlash in a couple of weeks.

UFlash is an editor and flashing tool for Ultimate/Incognito Ataris which does everything in-situ, allowing selective flashing of any ROM slot without disturbing neighbouring ROM content. 64KB sector flash ROMs are seamlessly handled by caching data in extended RAM, and the user follows an identical upgrade procedure to that employed for boards with 4KB sector ROMs.

ROM slot images (such as 8K BASIC, 16K BIOS and 256KB SpartaDOS X) can be retrieved from partitions on the PBI hard disk, as well as from mounted ATR images. It is even be possible to copy UFlash and and desired ROM images onto the FAT partition of a Compact Flash card on your PC, and launch UFlash direct from the SIDE loader. The tool then loads the ROM images straight from the FAT partition, using the same convenient file selector interface employed to browse HDD partitions, disk images and serial disk drives.

Slot descriptions can be edited and flashed to the ROM at any time, as well as exported to plain text files or imported from those same saved files. In addition, customized slot descriptions persist even when the BIOS (in which the description data is stored) is replaced.

The content of any slot, or even the entire 512KB ROM, can also be dumped to disk. Built-in file signature checks aim to ensure that failed flashes, bricked devices, and time-consuming ROM maintenance are things of the past. Using a hard disk, the entire 256KB SpartaDOS X slot can be updated in around one minute.

The above notwithstanding: while UFlash makes updating ROM slots as convenient as loading a file from disk, ROM flashes are still critical procedures, and a corrupted BIOS slot can still result in a bricked machine. For this reason, UFlash now supports Bright PLCCs as found in AtariMax flash cartridges, offering a further recovery path should the content of the original PLCC become corrupt.

Version 3 of UFlash provides support for the new Ultimate and Incognito BIOS, together with preliminary/experimental flashing support for the following devices:

  • SIDE/SIDE2 cartridge
  • MyIDE/Flash cartridge
  • MyIDE II cartridge
  • AtariMax 1Mbit cartridge
  • AtariMax 8Mbit cartridge
  • Sic! cartridge
  • IDE Plus (SDX ROM)


The latest version of UFlash can be downloaded via the following link:

Download UFLASH 3.20

Recent changes:

  • PCLink support added to the file selector
  • 65C816 compatibility