8 comments

  • eatonphil 2 hours ago

    Very cool! If you want to see a much simpler version of this I wrote an article a few years implementing a stack language in Postgres PL/pgSQL similar to what this one does.

    https://notes.eatonphil.com/exploring-plpgsql-forth-like.htm...

  • jpl56 25 minutes ago

    Lovely! (I saw a few examples in "tests")

    Next step : insert the Applesoft Basic assembly code and allow programming in Basic through SQL

  • Someone 6 hours ago

    This, basically, uses a table to store 64 kilobytes of memory, a single-row table for storing register values, and uses regular procedural programming to run the CPU (https://github.com/lasect/pg_6502/blob/main/init/05_execute....)

    I give that an A+ for perseverance, but I would have hoped to see something that uses the strengths of SQL more.

    For example, there could be a table with the decode ROM (https://www.cpcwiki.eu/index.php/MOS_6502#The_Decode_ROM_.28...) that could be used to drive the logic.

    Have a main loop that uses the inputs of that ROM to look up the output bits and update a table, and add triggers that handle each “micro-op”. A SQL engine could run those triggers in parallel until they hit a race condition, but those can be avoided a bit by having separate tables for each register.

    Even better would be if there were tables with every logic gate and wire in the original CPU, using a trigger to move the signals around. That would be a good test of the trigger handling in a SQL engine.

  • fred_is_fred 30 minutes ago

    Can someone take this and build a working 6502 binary that creates a SQL database?

  • larodi 2 hours ago

    Waiting for 6502 implemented on top of Sudoku!

  • m000 6 hours ago

    Cool! How about Postgres on MOS tech 6502 8-bit microprocessor powered by Microsoft's 6502 BASIC?

  • anthk 4 hours ago

    Kim-1 emulator and assembler for T3X0:

    https://t3x.org/t3x/0/sim65kit.html

    https://t3x.org/kimuno/

    Pocket calc as 6502 code

    https://t3x.org/kimuno/kimcalc.html

    T3x0 compiler to build the emulator:

    https://t3x.org/t3x/0/index.html

    I've got to run under OpenBSD/i386 but it needs a bit of tweaks in the Makefile. On the target section:

        # CFLAGS=$CFLAGS" -m32"                 # on x86 64-bit systems 
        CFLAGS=$CFLAGS" -static"                # in case all else fails
        CFLAGS=$CFLAGS" -fPIC"          # get rid of stupid linker errors
        CFLAGS=$CFLAGS" -Wl,-z,notext"  # get rid of stupid linker errors
        CFLAGS=$CFLAGS" -fno-PIE -no-pie"       # get rid of stupid linker errors
    
    Do the same in the bin/tx0.sh and bin/build.sh just in case. In my system I set the target to unix-386, and T3XDIR it's set to T3XDIR=/usr/local/t3x/lib in the Makefile and bin/tx0.sh scripts.

    Also, T3XBIN it's set to BINDIR= /usr/local/t3x/bin

    Then I ran:

          sh bin/modpath.sh /usr/local/t3x/lib 
          gmake all-native
          doas gmake install-native install-modules
    
    But it was still broken. Then, I edited /usr/local/t3x/bin/tx0 and set

    TX3DIR is above, and ditto with the four CFLAGS flags I posted.

    Just the ones at lines 38-42.

    OFC set PATH to /usr/local/t3x0/bin:$PATH in ~/.profile:

            export PATH=/usr/local/t3x0/bin:$PATH
    
    Yeah, it's tricky, but from now on everything will just compile with

          'tx0 foo' 
    
    where 'foo' it's a foo.t file.

    This was compiled under an Atom n270 CPU based netbook. I think the author uses a Pentium III machine. If T3X0 can do a MOS 6502 emulation that well, you can try expanding s65/sim65 to cover the Apple I emulation.

    And, as a plus, it might run fast on DOS 386 machines if s65/sim65 it's compiled a native binary.