Re: Ultima 3 "Mockingboard" version.

[Rubywand <rubywand@swbell.net>]

Linards Ticmanis writes ...
> 
> Rubywand wrote:
> > The C-64 definitely has better built-in sound than the 8-bit Apple II's.
> > You especially notice the difference in stuff like the opening song for
> > Alternate Reality. The Mockingboard's Programmable Sound Generator chip
> > gives an Apple II the same capabilities.
> 
> Does the Mockinboard contain any custom chips? Or is it something that
> could be cloned with a bit of dedication?
> 
 ....

     Mockingboard uses off-the-shelf chips. Music and sound effects are
produced using the General Instruments AY-3-8910 Programmable Sound Generator
(PSG). (Some Mockingboard models include a chip to produce speech. Pretty
sure these were also off-the-shelf items.)

     The 6581 Sound Interface Device (SID) chip used in the C-64 seems to
work almost exactly the same as the General Instruments PSG. I'm pretty sure
the 6581 is a proprietary chip.

     The PSG and SID can deliver three musical 'voices'. Mockingboard "Sound
II" (and some other models) have two PSG chips. This gives the Apple II user
two-channel sound and twice as many musical 'voices' as C-64 can produce.

     Besides the PSG, Mockingboard's use the 6522 for interfacing. A small
audio amp chip (think it's the LM380) is included to allow directly driving
speakers. (If you connect to an external amp, you can omit the LM380's.)

     So, yes; a Mockingboard for playing music and handling sound effects in
games like Ultima III would be fairly easy to build.



Rubywand