Malban – Vide diary – 9th of October 2016

Hi folks,

just a short notice of what I have been up to vectrex related. I admit I was not as industrious as in the past, but nonetheless I did some “small” things.

I updated the internals of PSG emulation to produce (and use) 16 bit data with oversampling, instead of the befor used 8 bit emulation.

The last couple of days I was quite busy listening and sorting YM-files, and the quality of the old routines left a lot to be desired. The new routines, while not “perfect” are quite a lot better.

Above you see some changes to ayi, which shows “larger” period numbers and on the bottom what I call a “ym-line” – for possible comparisson with a currently playing ym file.

I also enhanced the YM-Panel again a little bit:

Here you see the “player” tab (I did last week), the new feature is actually the second button on the top left. The tooltip says “insert data from a text file”.
I guess nobody else than me will ever use that button – but that is fine :-).

ASCII data in a file, like:

     $50, $00, $F0, $00, $40, $00, $18, $31, $00, $02, $02, $00, $00, $00
     $50, $00, $F0, $00, $80, $00, $18, $31, $00, $02, $04, $00, $00, $00
     $50, $00, $F0, $00, $B0, $00, $18, $31, $02, $01, $04, $00, $00, $00
     ...

can be read as “ym” data and are inserted into the current edited data.

While I see, that you might think that is not usefull – to me it was!
The last couple of days I setup a compile environment for MAME, the “MultiArcadeMachineEmulator”, and astonishing as it is, I succeeded compiling it.

Even more astonishing I persuaded the file “ay8910.cpp” to output ym-data!

(at the end of the method: ay8910_device::sound_stream_update(…) I inserted a few lines of “dirty code”:

  double tmp = machine().time().as_double();
  double dif = (tmp-skipper);
  tracker+= dif;
  skipper = tmp;
    while (tracker >= 0.02)
    {
        tracker -= 0.02;
        printf("$%02X",m_regs[0]);
        printf(", ");
...
        printf(", ");
        printf("$%02X",m_regs[13]);
        printf("\n");
    }

)

You get my meaning, this outputs ym-data at a 50Hz frequency, exactly the type of data I needed.

Now if you look more closely at the above YM-Panel screenshot, you might find the filenames I listed “interesting”.
Combine that with the fact that I wanted to do a “deluxe” version of a game I wrote for the vectrex some 18 years ago… – go figure :-)!(but don’t wait for it…)

Have a nice day…

Malban