Very impressive, and obviously a labour of love! As a calculator and SystemVerilog enthusiast, it's wonderful to see a project such as this come to fruition - congratulations!
replyI'm holding in my hand a 4-bit Von Neumann Mostek MK50310N that my father and I used to use to build calculators long ago. Although Mostek made chips for HP (such as the HP-35), they weren't commercially available, but the 50310 was. We could only dream of a project such as yours. I was happy when the "open source" NumWorks was released, but this project aligns more with my interests.
Will definitely install the Qt simulator - would be even better to build one IRL!
Re Numworks, at $125 for a calculator, you've got to really love the idea.
replyAt least the 6502 has a BCD mode built in!
replyI'd like to amplify this. Decimal math using nibbles containing 0 through 9 was standard operating procedure, one of the things that made the 6502 nice. Unfortunately you had to use a short loop to convert between 2s complement and BCD.
replyIronically the Z80 is a nibble ALU. That's why its so slow compared to the competition, an 8 bit add on a "2 MHz" Z80 takes as much clock time as a 8 bit add on a "1 MHz" 6809.
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