ASCII art demo with vintage HP 85 computer, HP 7970E 9-track tape and HP 2631G dot matrix printer

What do you with a 1970's vintage Hewlett-Packard computer, 9-track magnetic tape and dot matrix printer? Print ASCII art of course!

This is an unlikely assortment of a HP 85 scientific computer (1979), a HP 7970 magnetic reel-to-reel tape drive (1970) and a HP 2631 professional dot-matrix printer (1977). Although they all communicate via HP-IB, this is before a standard was established, and the higher end peripherals were not meant at all to connect to the diminutive HP 85 personal computer. In particular, the HP 7970 tape needs a bit of hardware help to talk to the HP 85. I had to make a modern equivalent of the HP 59401 using an FPGA board. It corrects bus parity on certain transactions on the fly, which curiously the HP 85 does not do properly. I called my contraption a "CM 59401" (CM for CuriousMarc of course). The original HP 59401 still remains in the setup, for the sole purpose of providing entertaining "Blinkenlights".

The program is essentially a driver for the mag tape, which I was able to cobble together in plain Basic, thanks to some very efficient low level HP-IB calls present in the (awesome) IO ROM.

The complete technical details of this demo including ASCII art files, FPGA device, HP-85 program and various utilities are available on my website here:
https://www.curiousmarc.com/demos/hp-...

Special thanks for this project go to:
Ansgar Kueckes (HP-IB mass storage Jedi, http://www.hp9845.net/9845/home/about... )
Everett Kaser (HP 85 grand master, http://www.kaser.com/hp85.html)
Carl Claunch (encouragement, fanfold paper, and FPGA baord Christmas gift - see, I used it! -, http://rescue1130.blogspot.com/).

More videos about the units used this project:
HP 2631G dot matrix printer restoration:    • HP 2631G Dot Matrix Printer Restorati...  
HP 7970E and other 9-track tapes:    • HP and Overland 9-Track Tape Drives Demo  
HP 59401A HP-IB analyzer:    • HP 59401A Bus Analyzer and HP 10342B ...  
HP 85 computer restoration:    • HP 85A Vintage Computer Repair