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

[Tom Wiltshire]

Whilst I applaud the effort and ingenuity that is going into these attempts to build modern top-octave generators, I don't understand the need.
The switch from separate master oscillators to one master osc and a top-octave generator chip caused a notable flattening in the sound of the instruments that did it, since everything got phase-locked together.
Wouldn't we be better off putting twelve surface mount oscillators on a chip? Or are you guys so far ahead of the original clock speed that it stops being such an issue? What are you intending to do with these chips? Just curious, not criticising.

T.

On 26 Mar 2012, at 23:23, Brock Russell wrote:

> 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.
> 
> 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
>>>>> 
>>>>> 
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> 
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