On Sun, 26 Aug 2007, Al Kossow wrote:
The GMD Reduction Machine used an HP 264x series
terminal with modified
firmware as an I/O device. Listings can be found at:
http://bitsavers.org/pdf/gmd/reductionMachine/terminal
Of particular interest is 2.file.pdf which appears to be firmware for
controlling the tape drives.
If you don't have the complete firmware listings of the HP 2648, I have
it. There are several binders that cover tape, graphics, terminal, I/O and
so on. I can try to scan it if you like. I also have the complete
maintenance manuals for the terminal and interface boards, including
schematics, but they are difficult to scan due to the paper size.
Christian