In 2012, Sebastian Bartkowicz (Candle) asked me if I could write a BIOS to realize the PBI hard disk functionality he was developing for the Incognito. During the months that followed, Candle thought of more and more things to add (such as the ability to read and write disk images mounted in the FAT partition of the CF card), and after weeks of coding and debugging, we had something approaching a final version.
In 2015, a desire to significantly broaden the functionality of Incognito and correct some problems with the PBI BIOS led me to completely re-write the the firmware for the device, including the main BIOS, PBI BIOS and XEX loader. Among new features provided by the firmware are the following:
- A PBI implementation of Matthias Reichl’s High-Speed SIO code which does not require OS patching and which works with external cartridges
- The ability to set the system date and time from inside the BIOS setup utility
- Expanded PBI BIOS settings on a dedicated menu page
- System information page showing video standard, CPU speed, etc
- User-selectable BIOS hotkeys
- Dual configuration profiles
- BIOS plugin API for user-defined external device control
- New, faster XEX loader supporting multiple FAT partitions, APT partition mounting and recursive searching
- SIO2BT support (at up to 56kb/s) and high-speed SIO for PCLink and other serial devices
- Built-in CIO “Z:” RTC device handler
The firmware consists of three separate files: the Main BIOS, PBI BIOS and SIDE loader. All three should be updated at the same time, and the machine power-cycled. As well the the ROMs, the archive contains UFLASH. Installation instructions may be found in the user manual.
The User Manual contains installation instructions and usage notes for the Main BIOS setup utility and SIDE/XEX Loader:
Technical documentation describing the firmware memory map and configuration data layout is provided below:
If wish to report any issues with the new firmware of have any suggestions on how it might be improved, you may email me directly via the address on the contact page, or post in the discussion thread on the AtariAge Forum.
SpartaDOS X 4.47 ROMs for Incognito
To complement the new Incognito BIOS, two sizes of SpartaDOS X ROM are provided (192KB and 256KB). The smaller (192KB) image allows flashing of the WIP Graphical OS alongside it. Both 192KB and 256KB SDX ROMs include the FDISK APT partitioning tool and other hard disk utilities on the CAR: device.
Use Tools->Set SDX Size in UFLASH to switch between available SDX ROM sizes prior to flashing. The 192KB setting enables the GOS in BIOS setup.
Original PBI BIOS and SIDE Loader
The APT BIOS for Incognito provides an OS-compliant PBI hard disk and high-speed ATR disk image mounting when SIDE Hardware is enabled in BIOS Setup. Note: PBI BIOS v.1.0 should be used only with Candle’s original Incognito main BIOS.
There are two ways to update the PBI BIOS in your Incognito. You can either use the 8KB ROM image for use with UFLASH, or the stand-alone upgrade utility. Both are included in the ZIP.
While it has been my privilege to write software for Ultimate 1MB, Incognito and SIDE, I enjoy no licensing agreements with hardware vendors. Nevertheless, since the PBI BIOSes and APT tools are integral to the functionality of these devices, please consider making a small donation (via the “Donate” button) to help ensure the continuation of software development and technical support. Donations also help with website hosting and equipment costs.