SynthModules

Hi All, 

Since it is summer, I have been working on my Vespa's and not 
spending time in the dungeon. But I did get some results before 
the nice weather set in.

The limitation on the Basic Atom Pro at the design time of the 
PSIM was the number of pins. Brice only had access to the 24 
pin version of the processor. That mean't the implementation 
had to use a very low I/O pin count. That fact (and economics) 
mean't the use of a serial DAC.

The transmit time for the serial DAC is the primary bandwidth 
limitation on the PSIM. The math coprocessor does 32 bit 
floating point math in one clock cycle. The actual calculation is 
very fast.

When the 40 pin version of the Basic Atom Pro comes out, you 
could add parallel DAC output. That will up the output rate by a 
whole lot and get the processor up into the audio range.

The 12 bit resolution of the DAC means each output step is 2 
millivolts. For most applications, that amount of zipper noise 
should be inaudible (inaudible stepping).

--- In SynthModules@yahoogroups.com, "mrboningen" 
<darkflametwentythree@h...> wrote:
> hi all. i see that there are various bits of software available 
which 
> turn the PSIM into an LFO/LFO's. i have a couple of questions 
about 
> this. 
> 
> firstly, how smooth are they at very slow rates, e.g. if you put a 
> really slow sine on the pitch of an oscillator, can you hear any 
> stepping?
> 
> next up, at the other end of the frequency spectrum, how do 
these 
> LFO's sound when driven into the audio rates? i know the PSIM 
is not 
> designed to do audio, but it must be possible? how does it 
sound? how 
> easy would it be to implement PWM etc.
> 
> cheers,
> 
> gregg.