SynthModules

John,

> I think I've got a pre-production unit. If there are any functional
> differences between these and the production units, please let me (or
> the list) know. Anything that would make software behave differently,
> for example. Thanks.

No.  There are absolutely no functional differences between the 
pre-production and production modules other than in the production modules, 
the I2C resistors are left off so we can use those two pins for other I/O 
(ie. the SpeakJet).  There are a couple of minor changes in routing of the 
traces... but other than that, solder mask and silkscreen is about it.  Any 
program written for the PSIM-1 will work on any PSIM-1 shipped.  I know 
several folks have requested a MIDI interface... and that's in the works.

> 3 words for you: Design for manufacturing. :-) Easier said than done,
> surely.

Yes, easier said than done.  I *thought* I was designing it for easy 
manufacturing... but I was thinking of it as how I would build it as a 
kit... not a bunch of them.  Yes, the PSIM-1 was originally designed as a 
kit (hence the extensive use of through-hole parts).  But if anyone has ever 
built a Blacet Time Machine... imagine building 50 of them in a row... only 
with more jacks and wiring.  heh  I *know* I should have designed the PCB 
for PCB mounted jacks (and yes Grant... I know... I know!)... but what's 
done is done.  Anyway, like I said earlier... once the first three 
prototypes were built, there were a few changes made on the next three.... 
and then onto production.  I don't like making changes to a PCB layout once 
it's been tested for fear of screwing something else up.  Ground loops, 
interference, etc. can be very difficult to troubleshoot.  So... using the 
philosophy that "if it works, don't fix it"... well, this is how it ended 
up.

Will I redesign the PCB for the next batch?  Probably... but not much.  I'll 
make wiring easier and probably go to surface mount for more of the 
components and SIP resistor networks where possible.  But, before I get 
ahead of myself... I need to finish this batch... and take a break to clear 
my head.  I'd just be happy with finishing up this batch of modules and 
making some music for a few weeks as I have a CD I'd like to finish. 
Somewhere between "hey, this would be a cool module" and "now"... I've 
learned a LOT about bringing a synth module from concept to production. 
Hats off to EVERYONE who has ever undertaken anything like this before.  I'm 
not saying I've walked miles in the shoes of John Blacet or Grant Richter... 
but I've tried on the shoes and some days they fit well... and other days 
they can be painful.  I've really enjoyed this project and the wonderful 
friends I've made and community we've built... and have full expectations 
that we'll see more from SynthModules in the future.

By the way, Basic Micro has released a new version of the IDE (programming 
software) we use for programming the PSIM-1.  It is version 7.2.0.6.  I 
recommend anyone who already has thier PSIM-1 download and install the new 
version.  Changes in this version include:

- Added FLOAT support to FOR/NEXT loops
- Added FLOAT support to MIN/MAX functions
- Fixed Conditional compiling bug(#IF/#IFDEF/#IFNDEF etc).
- Added FATAN2 command(syntax FATAN2 Yfloat\Xfloat,result, ie FATAN2 
1.0\2.0,result)
- Fixed FASIN/FACOS commands to handle -1.0 to 1.0(previously only supported 
0.0 to 1.0)

I'm excited about the the additional support for the FLOAT command as well 
as the FASIN/FACOS update.

Version 7.2.0.6 can be download here:
http://www.basicmicro.com/ViewPage.aspx?ContentCode=d_basicatompro

Anyway... off to work (day job building and repairing PCs)...

Take care everyone!
- Brice
http://www.SynthModules.com