Uploaded May 2025 | Updated September 2026, 2 weeks ago
To celebrate the 50th anniversary of the IBM 5100, we developed this capability demonstration of a demoscene-type side scroller for the PALM processor. Typically, only IBM CE/FE specialist were aware of the built in DCP (diagnostic control program) that allows direct setting of main memory (commonly called a "system monitor"). However, the PALM instruction set is described in the original IBM 5100 MIM documentation (Appendix C). In addition, after researching the IBM SCAMP prototype project that led to the IBM 5100, we found a 1972 document that fully describes the PALM instruction set - making this a contemporary processor with the Intel 4004/8008, but built using IBM's proprietary SLT (solid logic technology) fabrication (or "Dutchess" modules).
In general, the IBM 5100 is the closet one can get to the 1960s technology that ran the IBM S/360 and S/3 systems. But it has all the attributes that we are familiar with today in a personal/portable computer: boot up system software, keyboard input, video display, and a byte addressable memory space.
The IBM 5100 is also associated with the famous John Titor time travel story of c. 2001, which is later depicted in the Steins;Gate anime series c. 2011.
This is also a demonstration of the "daisy chain" multi-monitor output capability of the IBM 5100, using the BNC composite output video output jack on the back side of the system.
Because the BASIC (and APL) of this system faithfully replicates the "line printer" style of interactive usage, this type of (side scroller) program is not possible using this system's BASIC or APL software. And there is onboard support for anything like VT52/VT100, etc., so this is not just using any kind of escape-sequence parsing. The 64x16 CRT screen display is mapped to a region of main memory. And so, a custom machine code program can be loaded and perform logic operations that manipulate this memory region (a convention later used on the Commodore PET and subsequent systems).
A BASIC-only 16KB configured IBM 5100 was price listed at about $6500, which included the 200KB capacity DC300 data storage tape (which had more capacity than the 8" floppy disks at the time). Other vendors (like 3M) later released QIC DC61250 tapes, that used the same format and double the storage capacity (without requiring any system or ROM changes).
A deeper look of the PALM assembly code used for this software will be prepared after the June VCF Dallas 2025 event.
NOTE: We've gone back and forth on whether this should be called a "vertical side scroller" or "horizontal scroller" :)
The sound bites near the middle of this video are clips from the Steins;Gate series, of each of the three main characters.
For a discussion on the SCAMP prototype:
https://voidstar.blog/scamp-a-review-50-years-later/
For a discussion about this specific program, see:
forum.vcfed.org/index.php?threads/ibm-5100-side-scroller-presentation-new-palm-machine-code.1253061
Tech docs, code, and notes are also here:
github.com/voidstar78/IBM_5100_DOCS/tree/main/SIDESCROLLER
And for my discussions on the IBM 5100:
https://voidstar.blog/ibm-5100-personal-computer/
youtube.com/watch?v=JIJNrBaTenM
To celebrate the 50th anniversary of the IBM 5100, we developed this capability demonstration of a demoscene-type side scroller for the PALM processor. Typically, only IBM CE/FE specialist were aware of the built in DCP (diagnostic control program) that allows direct setting of main memory (commonly called a "system monitor"). However, the PALM instruction set is described in the original IBM 5100 MIM documentation (Appendix C). In addition, after researching the IBM SCAMP prototype project that led to the IBM 5100, we found a 1972 document that fully describes the PALM instruction set - making this a contemporary processor with the Intel 4004/8008, but built using IBM's proprietary SLT (solid logic technology) fabrication (or "Dutchess" modules).
In general, the IBM 5100 is the closet one can get to the 1960s technology that ran the IBM S/360 and S/3 systems. But it has all the attributes that we are familiar with today in a personal/portable computer: boot up system software, keyboard input, video display, and a byte addressable memory space.
The IBM 5100 is also associated with the famous John Titor time travel story of c. 2001, which is later depicted in the Steins;Gate anime series c. 2011.
This is also a demonstration of the "daisy chain" multi-monitor output capability of the IBM 5100, using the BNC composite output video output jack on the back side of the system.
Because the BASIC (and APL) of this system faithfully replicates the "line printer" style of interactive usage, this type of (side scroller) program is not possible using this system's BASIC or APL software. And there is onboard support for anything like VT52/VT100, etc., so this is not just using any kind of escape-sequence parsing. The 64x16 CRT screen display is mapped to a region of main memory. And so, a custom machine code program can be loaded and perform logic operations that manipulate this memory region (a convention later used on the Commodore PET and subsequent systems).
A BASIC-only 16KB configured IBM 5100 was price listed at about $6500, which included the 200KB capacity DC300 data storage tape (which had more capacity than the 8" floppy disks at the time). Other vendors (like 3M) later released QIC DC61250 tapes, that used the same format and double the storage capacity (without requiring any system or ROM changes).
A deeper look of the PALM assembly code used for this software will be prepared after the June VCF Dallas 2025 event.
NOTE: We've gone back and forth on whether this should be called a "vertical side scroller" or "horizontal scroller" :)
The sound bites near the middle of this video are clips from the Steins;Gate series, of each of the three main characters.
For a discussion on the SCAMP prototype:
https://voidstar.blog/scamp-a-review-50-years-later/
For a discussion about this specific program, see:
forum.vcfed.org/index.php?threads/ibm-5100-side-scroller-presentation-new-palm-machine-code.1253061
Tech docs, code, and notes are also here:
github.com/voidstar78/IBM_5100_DOCS/tree/main/SIDESCROLLER
And for my discussions on the IBM 5100:
https://voidstar.blog/ibm-5100-personal-computer/
youtube.com/watch?v=JIJNrBaTenM
