A programmable scientific calculator design project

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Web site first published elsewhere on: 26-FEB-2000 (Am I slow, or what?)

Last hacked up on: 09-JAN-2003

This page is being totally rewritten, as there have been so many changes since the last update.  All kinds of things went wacko, and in the end I never was able to get a decent replacement for my stolen laptop.  I found a couple of surplus Fujitsu Point 510 pen tablets running with AMD 5x86 [pretty much like a 486] chips at a whopping 100 Megahertz...  They were REALLY low in price when I bought them (I think they were like US $114 each) and I figured that I would have to swap parts back and forth to get one working.  The good news is that I have two working.  The rough part has been that I haven't scrounged up a connector to fit the expansion port, so I can't drive the MegaMax device programmer that I love so much.  No USB either, and I can't add a PCMCIA/PCCARD to add USB since they all seem to be of the 32 bit CardBus flavor, and the little 510's single slot is old standard 16 bit.

Sooo...   I thought that since the device programmer is DOS based, why not try it on my little Sharp PC-3000 DOS based handheld?  Unfortunately, the software must require either extended memory or else uses 286/386/486/Pentium instructions.   It won't run on my little handheld.  So what else is new?

I managed a really bad design of the little circuit that manages the battery backup for pseudo-nonvolatile RAM, so I'm reworking it.  It's red 5x7 LED's all the way!

If you like things of the calculator sort, take a look at the: HPCC: Handheld And Portable Computer Club They have a lot of interesting information and also many related links.