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

Posted: Tue Mar 31, 2015 1:06 pm
by Anarkand
thanks for clearing that up :) - it accepts 256 k cards.

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

Posted: Fri Apr 10, 2015 6:29 pm
by Anarkand
Not be be impatient. But how is it going guys :)

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

Posted: Fri Apr 10, 2015 6:37 pm
by ʝɵʝɵ
You have been doing this before and I stop finding it funny by now. If we don't post any progress, there isn't any. Dojoe is waiting for the parts to arrive and to find some spare time to assemble the new cards, after that you will get some news. Don't ask for updates until he makes a new announcements, this is just rude. We have lifes, too, and already invest as much spare time into this project as we are willing to. Your asking for status updates when there is nothing to update just takes aware more of this spare time.

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

Posted: Mon Apr 13, 2015 3:09 pm
by Zaichornok
Great project Guys.
Put me down for a couple of these.
Rob in London, UK.

Rev.B PCBs

Posted: Tue Apr 14, 2015 9:56 pm
by dojoe
So, an update.

I received six Rev.B PCBs in the mail -- here's one of them in all its glory:

Image

They're as long as the original cards now and a little slimmer at the connector end so as to not destroy your precious card slots ;) Also, the labels are tidied up a little and should be pretty self-explanatory now.

Question: Would you guys understand how to operate a 256 variant as well as a 512 variant just going by these labels?

I ordered parts to build a few Rev.B cards and they will likely arrive tomorrow, but my weekends are pretty full lately, so I don't think I will have time to actually build any cards before May. Also, I want to complete the test fixture I have in mind so I can test the cards before sending them off to beta testers.

I'll keep you guys posted -- thanks for your patience! And thanks for your huge interest in our little project here, that's what keeps me going.

Re: Rev.B PCBs

Posted: Tue Apr 14, 2015 11:25 pm
by baz99
dojoe wrote:Question: Would you guys understand how to operate a 256 variant as well as a 512 variant just going by these labels?
Looks clear to me! ;)

And that PCB looks even better than the first one! =D>

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

Posted: Wed Apr 15, 2015 7:58 am
by Anarkand
Wow. It is really beautiful. I don't think it would be obvious by the look of it, I see a 256 inscription and a 512 inscription. At closer inspection it looks like either 4 x 256 banks, or 2 x 512 banks. And these are then ordered in 4 a/b/c/d banks.

Happy to supply interest.

Good work

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

Posted: Wed Apr 15, 2015 12:35 pm
by Zaichornok
Hey dojoe - looks fantastic.
I am not quite clear how to select banks, but obviously it is a combinations of SW2 ans SW3 settings right?
I have no doubt it will be simple to remember once you explain. :roll:
By the way, I plan to use this for the Roland R880 professional studio reverb. It's a bit of a rare one but still has many dedicated users globally. Was very poular in Germany, and the USA. It uses the 128, 256 and the 512 cards.
Would love to do a beta test with your card and the R880, and happy to pay for the test card up front.
Rob

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

Posted: Wed Apr 15, 2015 1:26 pm
by Zaichornok
I meant to add in my last post, that you talked earlier about cost / volume.
One memebr suggested sales of 100 units per year. I would guss at least 5 to 10 times that, or more, if you get the price right, and once word gets out. Just listing the card on eBay would sell hundreds very quickly. The demand for original cards is still there in a very big way. If you want any help /participation in selling your card let me know.
Also, I know you touched on this subject some time back, but how susceptible would the card be to normal handling / static?

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

Posted: Wed Apr 15, 2015 11:19 pm
by dojoe
baz99 wrote: And that PCB looks even better than the first one! =D>
Gee thanks, and that from someone who should know :mrgreen:
Zaichornok wrote: Hey dojoe - looks fantastic.
Hey Rob -- thanks! :D
Zaichornok wrote: I am not quite clear how to select banks, but obviously it is a combinations of SW2 ans SW3 settings right?
I have no doubt it will be simple to remember once you explain. :roll:
Yep, SW2 and SW3 together select one out of 16 banks for the 256 model and 8 banks for the 512 model. The banks are A1, A2, A3, A4, B1, B2, ..., D3, D4 for the 256 model. For the 512 model, 1 and 2 are the same bank, as are 3 and 4.

I guess the labels serve as more of a reminder than a full user guide :roll: Don't worry, I'll put up a FAQ/docs when I'm ready.
Zaichornok wrote: By the way, I plan to use this for the Roland R880 professional studio reverb. It's a bit of a rare one but still has many dedicated users globally. Was very poular in Germany, and the USA. It uses the 128, 256 and the 512 cards.
Would love to do a beta test with your card and the R880, and happy to pay for the test card up front.
That can likely be arranged; afaict you're the first R880 user in here. As for my usual question: Any chance you might supply a photo of an original RAM card sticking in the GC-8, so I can see if there might be any issues with my card? Google image search let me down this one time =(
Zaichornok wrote: One memebr suggested sales of 100 units per year. I would guss at least 5 to 10 times that, or more, if you get the price right, and once word gets out. Just listing the card on eBay would sell hundreds very quickly. The demand for original cards is still there in a very big way. If you want any help /participation in selling your card let me know.
I might just take you up on that some day ;)
Zaichornok wrote: Also, I know you touched on this subject some time back, but how susceptible would the card be to normal handling / static?
tl;dr: I wouldn't worry too much about it as long as you keep the card either plugged into a synth or inside the static shielding bag I'm shipping it in.

Detailed EE musings follow, feel free to ignore:

I haven't tested this, but modern ICs are usually way less susceptible to static discharge once they're built into a circuit. This is due to internal ESD protection diodes that deflect any static discharge to the power supply rails, where it's soaked up by the omnipresent decoupling capacitors. So you should generally be fine.

Given sensible handling, the most probable entry point for static discharges will be the shell of a switch, so it would make sense to tie those to ground. That'll give the static charge a nice low-resistance path to leave.

The Rev.B boards don't have that, but the shells are floating instead. The upside of this is that the static charge is less likely to discharge at all since the shells are isolated, which means less ouchies ;) The downside is that if it does discharge, it might hit a signal wire and enter an IC, but there's still the protection diodes protecting the IC, so the chance of harm is low.

When the card is unplugged, it is generally a good idea to handle it with care and be careful not to touch the contacts, not only for static discharge reasons but also because you don't want your fingerprints on them -- sweat is slightly corrosive and might harm the contacts over time. I'll ship every card in a static shielding bag, and I highly recommend storing it in there while not in use.

Over all, the Rev.B cards should be mighty fine as they are, but I'll consider grounding the shells for the next batch of boards. Thanks for making me think about this ;)

(Also, this is SO going into the FAQ :lol: )

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

Posted: Thu Apr 16, 2015 8:14 am
by ʝɵʝɵ
And if empirical evidence if of any use, my card is still working after two months of operation, no static discharges so far! :D

And damn, that rev.B does look good. Kinda makes me want to get another card at some point... :D

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

Posted: Sat Apr 18, 2015 8:10 pm
by SoundWerx
So pumped about this project. I recently bought two NOS Roland 256-E cards from Australia and paid around $115 NZD each for those. I have a lot gear that will happily support these cards. 3x D-50's, 4x JD990's and 2x JV-2080's.

Thanks again for kicking off a great project and for keeping with it :)

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

Posted: Mon Apr 20, 2015 9:40 pm
by the synthman
Brilliant idea. I would be interested in a 256E replacement for my Roland R-70 if possible. The ones on ebay are bloody expensive.

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

Posted: Tue Apr 21, 2015 10:18 am
by Zaichornok
Hi Dojoe, I have those photos of the Roland R880 GC8 controller card slot.
How should I send the jpg's to you?

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

Posted: Tue Apr 21, 2015 1:28 pm
by ʝɵʝɵ
You could upload them to imgur.com; alternatively, there's an "upload to tinypic" option if you use the "post reply" button.