[sdiy] Digital delay memory

[Tom Wiltshire]

Personally, I've being trying to out-do the PT2399 - shouldn't be too impossible, right?!? But it implies a through-hole chip, and as close to a single-chip solution as I can get. As such, the dsPIC and an external SRAM isn't a bad fit.

Of course, if I go to SMD there are a million better quality options - higher powered processors, better codecs, bigger RAMs. But where's the fun in that?

I'd like to produce a DIYer-friendly digital delay chip that could be used in stomp boxes and/or synths and which could produce longer, better quality delays than the PT2399. I think it's doable. I've got some reasonable hardware on stripboard, and I'm working on the firmware. With a bit of luck, I can chuck a few extra features at it.

I'll keep you posted.

Tom


On 27 Apr 2016, at 19:29, Jay Schwichtenberg <jays at aracnet.com> wrote:

> I've been thinking about doing some DSP stuff and delay line stuff with the
> newer MicroChip PIC32MZ series of processors. They're not really cheap but
> have up to 512K bytes of internal RAM and an I2S interface. When start to
> think about putting something together with SPI RAM with your time, board
> space and PCB development then to me the extra cost becomes trivial.
> 
> https://www.olimex.com/Products/PIC/Development/PIC32-HMZ144/resources/PIC32
> -HMZ144_UM.pdf
> http://www.digikey.com/product-detail/en/olimex-ltd/PIC32-HMZ144/1188-1160-N
> D/5247127
> 
> We see a lot of little ARM boards come out like the Teensy/Arduino for
> example. I'd like to see something like that with a higher end ARM chip on a
> bigger board with USB and bootloader, external fast ram and more pins broken
> out. That to me would be a good basic platform for doing a whole lot of
> stuff. Main problem for hobbyists like us is most ARM chips that have an
> external memory interface are in BGA (Ball Grid Array) packages. These would
> require some form or reflow soldering. Some people have used toaster ovens
> and hot plates to do that but it sounds pretty tricky for the average
> person. Also the boards would probably have to be more than 2 layers with
> buried and blind vias.
> 
> Good luck.
> Jay S.