[sdiy] programmable synth module

[Bahamut]

Someone did a very nice mod to their PSIM that interfaced an LCD display to 
it.
http://modularsynthesis.com/modules/synthmodules/PSIM-Display/PSIM-Display.htm

This would be handy if you expand the program ram so you could have all of 
your programs preloaded.

That way the lcd display could let you know which program you were on and 
what various ins and outs do.

 As it is now if I load 4 programs into its program ram and swap between 
them its easy to forget
which program I'm on and what the various ins and outs are set up to do.

Chris



----- Original Message ----- 
From: "john mahoney" <jmahoney at gate.net>
To: <synth-diy at dropmix.xs4all.nl>
Sent: Saturday, February 11, 2006 2:32 PM
Subject: [sdiy] programmable synth module


> There's a module called the PSIM-1 that you can see at
> http://www.synthmodules.com/.  A small number of PSIM-1s exist, but it's 
> not
> what you'd call "readily available," which is too bad because it's a 
> really
> cool module. As cool as it is, though, it did have room for improvement.
> Let's look at the PSIM-1 for inspiration and try to invent a new version 
> of
> a programmable synth module.
>
> The gist of the PSIM-1 is this: 4 analog inputs that feed an
> analog-to-digital convertor; 4 analog outputs fed by a digital-to-analog
> convertor; and, in between, a programmble microprocessor running the show.
> It's possible to add MIDI inputs and outputs, too. There are Start, Stop,
> and Reset buttons on the Frac Rac front panel, as well as 4 LEDs that show
> the output level of each of the 4 analog outputs. There's also a fifth
> output called Aux which can be used for certain things. I think the ADC 
> and
> DAC each have 10-bit resolution.
>
> The PSIM-1 is programmable using a variant of the BASIC language; code is
> written on a PC and loaded to the module. Programs load into Flash memory 
> so
> that you only need to hook up a PC when you want to load the module with 
> new
> code. A program was even developed that allowed you to load multiple
> programs at once and select them using front panel buttons.
>
> The PSIM-1 is capable of limited audio generation, but it's really too 
> slow
> for most audio generation and audio processing tasks. It's more of a
> programmable control voltage processor and function generator.
>
> The difference between a device that can handle audio and one that's 
> limited
> to CVs can be quite large -- this ain't no DSP! So, although it's tempting
> to have audio capability, I would rather have a lower cost CV processor 
> than
> an expensive, programmable DSP module. And there is definitely a pent up
> demand for something like the PSIM-1.
>
>
> So, what can be improved over the PSIM-1? Here's a starting list:
> -- more RAM
> -- built-in MIDI in/out
> -- more program memory
> -- ADC and DAC optimized for handling pitch CVs (sufficient resolution,
> etc.)
>
> What's right about it?
> -- direct-coupled analog ins and outs
> -- versatile!
> -- fairly easy to program
> -- reasonable cost (they were $300)
>
> What features would be nice?
> -- ability for module to write data to flash memory
> -- additional inputs and outputs
> -- pluggable memory cards like Compact Flash or SD or something (the
> cheapest ;-)
> -- expandable RAM
> -- faster processing is never a bad thing
>
>
> Any suggestions for a core? Is the BasicATOM chip still the best way to go
> for something like this?
> --
> john
>