[sdiy] CPLD shield for arduino/AMANI 64/AMANI GT

[nvawter at media.mit.edu]

Quoting Brock Russell <brockr0 at shaw.ca>:

> I see, you're not making an MK50240 clone exactly, but making a  
> usable top octave generator. That still seems to be quite a trick to  
> get the design done to that few cells. I've been thinking of going  
> in the opposite direction, using a higher frequency clock and a ten  
> bit counter, but the MK50240 type clones I designed use the same  
> divisors as the original.
>
> I haven't soldered the Green PAK2 DFNs. I haven't made any boards  
> yet as I can't make boards myself with toner transfer that have  
> 0.4mm pitch parts and I didn't really want to make some single  
> design boards. I finally decided over the weekend to make some DIP  
> adapter boards that have battery back up so I can prototype with a  
> bunch of devices without having to permanently program the OTP  
> parts. The Silego development kit is two parts, the socket board  
> plugs into the main board, so I'm making a different socket board  
> with a DIP ZIF socket to handle the adapter boards. I should have  
> that up and running in a couple of weeks.

yeah, the MK50240 does huge divisions...  something like 256-512, or  
8-9 octaves down.  my divider design does between 16 and 32 or 4-5  
octaves down...

My friend and I are trying to make an arpeggiator for arbitrary audio  
input, so for this task, too much division may be a disadvantage.   
We're planning to use a PLL in a stage before the divider...

So we can't get mk50240s anyway and I figure it's more reliable to less
frqeuency multiplying and less dividing...

So it's not really for an organ...    We probably won't even use  
multiple outputs simultaneously..  in our recent design sketches, a  
mux selects one of the simultaneously-available outputs at a time...    
in my experience, organs sound better with imperfect harmonic  
frequencies, so I could see how using a string of perfect dividers  
would result in a more sterile flavor.

One other fun thing I'm excited about is to use a reset pin on the TOG  
to jam 0s into all of the dividers.  It should be useable as a type of  
sync signal to the audio!  No guarantees, but looking forward to the  
experiment!  My Altera hardware is still in the mail, but my 4046 PLL  
just arrived in the mail today!  and I've designed a first draft of  
PCB for experimenting with it!!!

here's my board layout, if anyone has critiques or tips:
https://docs.google.com/file/d/0B27wuPBwl_tbOUFlUEJlYllUakNqTFEyaGN6eExPQQ/edit

and here's the schematic, based on someone else's design, which is  
annotated on the schematic:
https://docs.google.com/file/d/0B27wuPBwl_tbYkRhb2lhYmtTTkdxNFBDR0NWN09JZw/edit

I checked http://protoadvantage.com to see about their DFN adaptor  
boards for possible use with Silego parts.  Seems possible, but they  
don't have the perfect part...   they do claim to make new adapters  
upon request, though!





> Brock
>
> At 10:12 AM 26/03/2012, nvawter at media.mit.edu wrote:
>> Heya!!
>>
>> Glad you noticed- it took a lot of work.  49 was my estimate, but my
>> first draft uses 56 of the cells.  Cutting it close!  It has not been
>> simulated yet, because I need to learn how to simulate in Quartus.
>> The two approaches I used are to compute the minimum accuracy needed
>> and to organize the dividers into a tree of chains that have common
>> divisors!
>>
>> hmm checking out Silego programmable parts now.  interesting.  some
>> nifty analog components inside those little devices, including an ADC.
>> They might not be so bad for DIY..  they have free development
>> software for Win as well as OSX.  They also sell dev sockets.  And,
>> they have lots of how-to videos and a $50 dev kit.  They haven have a
>> design library for OrCad and Eagle!  Intriguing!
>>
>> Did you end up solder-mounting your Silego DFNs?
>>
>> Quoting Brock Russell <brockr0 at shaw.ca>:
>>
>>> I'm kind of late picking up this thread but I have to ask, how do
>>> you create a top octave generator with only 49 cells in a CPLD? The
>>> Altera EPM3046A has one flip-flop per macro cell so it seems to me
>>> you'd need two of these devices to generate 12 notes.
>>>
>>> I designed a few MK50240 clones a few months ago using 3 and 4
>>> Silego SLG46400 Green PAK2 devices and some CD4504 level shifters.
>>> It's actually possible to make a DIP sized plug in replacement. The
>>> Silego parts aren't really DIY friendly as they are 2.5mm square 12
>>> pin DFNs, but they are very cool devices containing a ton of
>>> features in a 28 cent part.
>>>
>>> Brock
>>>
>>>
>>> At 08:27 AM 15/03/2012, nvawter at media.mit.edu wrote:
>>>> Oh, heck yeah!
>>>>
>>>> My friend and I are currently obsessed with recreating chromatic clock
>>>> divider chips.  I think a CPLD would be great for that.
>>>>
>>>> The Altera EPM5064 on that Arduino CPLD shield has 64 macrocells.  My
>>>> estimate for a single octave MK50240 clone is about 49 cells.
>>>>
>>>> anyone have any other ideas for MK50240 clones that are available  
>>>> in stock?
>>>>
>>>>
>>>>
>>>>
>>>> Quoting dan snazelle <subjectivity at hotmail.com>:
>>>>>
>>>>> are there any SYNTH DIY uses for a CPLD/programmable logic?
>>>>>
>>>>>
>>>>> http://majolsurf.net/wordpress/?page_id=368
>>>>>
>>>>>
>>>>>
>>>>>
>>>>> http://majolsurf.net/wordpress/?page_id=1663
>>>>>
>>>>>
>>>>> _______________________________________________
>>>>> Synth-diy mailing list
>>>>> Synth-diy at dropmix.xs4all.nl
>>>>> http://dropmix.xs4all.nl/mailman/listinfo/synth-diy
>>>>
>>>>
>>>> _______________________________________________
>>>> Synth-diy mailing list
>>>> Synth-diy at dropmix.xs4all.nl
>>>> http://dropmix.xs4all.nl/mailman/listinfo/synth-diy
>>>
>>
>
>