A new old bug in the printer ROM?

[brouhaha]

(10-23-2023 11:21 AM)Tinue Wrote:  Thank you for this inside view on the development of the DM41X!

Sorry, that's not what it was. I was not involved in the DM41X development in any way, and have no association with SwissMicros other than being a customer. Anything I say about the innards of the DM42 or DM41X is my own speculation, though in the area of DM41X infrared printer support, I'm fairly confident in what I've said.

All information I posted was based on my own experiences, engineering prototypes in conjunction with the late Richard Ottosen, that were functionally similar to the DM42 and DM41X. We developed our specific Free42-based and 41-microcode-based prototypes in 2010 to 2012, after having made a series of simpler HP-microcode-based prototypes earlier. I've shown those off at many of the annual HHC conferences. Anyhow, the point being that Rich and I faced some of the same challenges that the engineers at SwissMicros have, and we used the same approach to IR printer support on the 41.

We never made it past prototype stage because we never were able to fund having high-quality casings, keys, etc. manufactured, although we used the same Sharp Memory LCD as the DM42 and DM41X have subsequently used. Rich and I were only developing calculators we were interested in, because no one else was doing it. Once SwissMicros introduced the DM42, which satisfied my desires and partially satisfied Rich's, we felt much less need to try to commercialize what we had. I am very impressed that SwissMicros has actually succeeded in making calculators with a good industrial design, which at this late date is far more of a challenge than writing the firmware (in my opinion as a long-time firmware developer) (when leveraging already-available Free42 source code, or HP-41 microcode).

That hasn't, however, stopped me from working with another friend, John Doran, to develop a one-off (well, actually two-off) Nixie tube calculator running microcode from (and thus simulating) the HP Woodstock and Spice series calculators. We presented that at the recent HHC 2023, and I expect that Eric Rechlin will have the video up on Youtube within the next few weeks. John and I aren't going to be building any more units of this design, but we will make the plans publicly available, including schematics, PCB layouts, and software source code.