HP-19C Print

[brouhaha]

(02-03-2023 04:44 AM)teenix Wrote:  .
Just wondering if anyone knows whether the HP-19C always prints using full line widths or just partial ones for smaller print lines like if was to do a PRX with 0.00 on the display.

That surprised me when I got the 19C microcode working in Nonpariel a few months ago. I don't have a real 19C at hand for comparison, but it appears to be the intended behavior. Given that the same PICK chip (or PIK, HP wasn't consistent) as the 97 is used, if there's a physical limitation of the 19C printer mechanism, then the microcode must be written to work around it. Since huge portion of the 19C/29C microcode are directly copied with little or no change from the 67/97, it seems unlikely that they would have changed the printing microcode unless the hardware required it.

The same engineer, William Egbert, wrote much of the microcode for the 67/97 and 19C/29C, designed the motor driver circuit for the printer used in Topcat and Sting calculators, and wrote a series of HP Journal articles on calculator algorithms.