Custom-built multi-bank Roland M-256/M-512 memory cards

[ʝɵʝɵ]

I would def be interested in this, as most cards for my roland d110 are way too cheesy, and getting one on ebay is more expensive than the unit itself...

Just to be sure, we're talking about RAM cards for patch data. "Way too cheesy" sounds like you are talking about PCM cards, of which I don't know if they work identically, i.e. if they have the same pinouts. Then again, I suppose dojoe could propose a similar test as for the M-512E card to find that out. Maybe that would make it simpler to create PCM cards, although of course you'd still have to know the sample format and header layout on the ROM chip to actually create a real PCM card...

[dojoe]

So yes, it looks like contact 17 carries the highest address bit on the M-512E card.

That it does, thanks for measuring!

I am almost done with the board layout, but right now, other (real-life) stuff has priority. I'll keep you posted when I make further progress

[baz99]

I am almost done with the board layout, but right now, other (real-life) stuff has priority. I'll keep you posted when I make further progress

Sounds good, I'm looking forward to it. Are you already able to give us an estimate how much the card will cost?

[heimhelicopters]

Hi,

interesting project! I have 2 D-70 synths and a 512e ram card. And a few sets of sounds on my atari emulator. Would be nice to put them all in a multi ramcard and work from there. I'm going to toggle pin 17 between 0 volt and 5 volt first to take full advantage of my 512e card.
Are you going to share the board layout's?

Just to be sure, we're talking about RAM cards for patch data. "Way too cheesy" sounds like you are talking about PCM cards, of which I don't know if they work identically, i.e. if they have the same pinouts. Then again, I suppose dojoe could propose a similar test as for the M-512E card to find that out. Maybe that would make it simpler to create PCM cards, although of course you'd still have to know the sample format and header layout on the ROM chip to actually create a real PCM card...

According to the schematics of the D-70 the PCM and DATA cards have the same pinning. The format will offcoarse be totally different. Would be nice though to make our own PCM cards with unheard of, new sounds fitting the 2015th.

Greetings from holland

Steven

[xxxyyyvvv]

I would def be interested in this, as most cards for my roland d110 are way too cheesy, and getting one on ebay is more expensive than the unit itself...

Just to be sure, we're talking about RAM cards for patch data. "Way too cheesy" sounds like you are talking about PCM cards, of which I don't know if they work identically, i.e. if they have the same pinouts. Then again, I suppose dojoe could propose a similar test as for the M-512E card to find that out. Maybe that would make it simpler to create PCM cards, although of course you'd still have to know the sample format and header layout on the ROM chip to actually create a real PCM card...

I know, i just did not translated well enough what i meant to say. Having a card for storing patches would be killer! PCM ones are meh, i dont use "realistic" instruments at all.

[SoundWerx]

Hello. I would most definitely be interested in purchasing such a card, I'd probably buy two. I have 2x D-50's, 4x JD-990s and 2x JV-2080's so this idea is very appealing. I hope the project comes to fruition!

Rob
New Zealand

[dojoe]

Newsflash!

I have completed the PCB layout now and sent it to the manufacturer (oshpark.com, they're great for small DIY projects!); I should have three prototype boards come January. I already have all the parts, so I should be able to complete the first card in January and get together with ʝɵʝɵ for testing.

Are you already able to give us an estimate how much the card will cost?

The raw PCB costs $11, the MRAM chip itself goes for $24 to $39, depending on what Digikey has on stock (Coincidentally, a much larger MRAM chip that'll allow for 64 banks wouldn't be much more expensive, but try and manage that many banks ). Add $5 for miscellanea, $15 for my effort (design, procurement, assembly, testing, shipping) and an estimated $10 for shipping and we end up at a rough estimate of $80, or €65.

If you go for the 4-bank variant (2 banks for M-512 mode), the MRAM costs $13, so take $25 off the estimate above for $55 / €45. (I could theoretically build a single-bank variant for $50, but who wants that? )

Those are one-off prices -- I'm assuming there won't be enough interest to go for high volumes It's more than you pay at Ebay for an M-256, but it's brand new, 16 times the space, and doesn't need batteries.

[baz99]

Sounds good, I would prefer the larger version (the one you estimate at 65 Euros).
By the way are you EU or US based?
Just asking as I will have to take customs and import taxes into account if you aren't in the EU.

Those are one-off prices -- I'm assuming there won't be enough interest to go for high volumes

I think you underestimate demand, my guess would be you could easily sell a batch of 100 within a year, there are so many JV1080 and 2080 out there.

[Marpytoys]

For my vdrum td10 I'm looking for a replacement of M-512E card.
Any idea yet when it will be available?
A schema how to do it myself is fine as well.

[dojoe]

Sounds good, I would prefer the larger version (the one you estimate at 65 Euros).
By the way are you EU or US based?
Just asking as I will have to take customs and import taxes into account if you aren't in the EU.

EU, no worries

I think you underestimate demand, my guess would be you could easily sell a batch of 100 within a year, there are so many JV1080 and 2080 out there.

You and the others in this thread would definitely get hand-assembled prototypes and we'd see how they turn out and whether we need any fixes for specific synths or something. Once that's ironed out, I might consider running a small batch; luckily there are professional assemblers out there who will do small batches for slightly less than a fortune.

For my vdrum td10 I'm looking for a replacement of M-512E card.
Any idea yet when it will be available?
A schema how to do it myself is fine as well.

Let's say March -- I'm doing this on my spare time which is kinda limited. I should have the first unit complete and ready for testing in January, and then I need to get together with jojo for testing, potentially fix problems, order parts and PCBs, build them, ship them...

[baz99]

Excellent, I'm looking forward to it!

[SoundWerx]

Terrific news! I've been periodically checking this thread hoping to hear more. I'd most definately be lining up as a customer. I'll keep checking back periodically. Thanks for continuing on with this great project!

[db0451]

I'll be interested in buying one or two of these.

[dojoe]

Happy new year, everyone! I bring good news:



The bare boards came in the mail yesterday Barring any disasters (like the last missing parts not arriving by Friday), I should be able to build the first prototype this weekend and ship it off to jojo for testing.

I'll keep you posted.

[baz99]

I'm impressed, they look very nice!

Happy new year to you too!