I tend to believe that it's worth the effort to make it dynamic. �A static rom would mean having �a hardware burner to create it. �If we have �a solid plan I think it's doable.
Hardware, I think we should be using an atmel AVR chip, they are small low powered and fast enough to pump everything through. �They also can deal with SD cards
easily, and possibly USB.
We also need some RAM on board for fast access to the samples. �I think 64mb is the largest sized rom? �Or is it 128mb? a four layer card, some resister packs. �
Is there a crystal on the expansion cards or is it clocked by the EMU?
Are there any standard IC's on the ROMs or are they all proprietary EMU?
From the software side of things we need to reverse engineer some of the actual stored formats, like patches, beats, and riffs. �We should be able to deliver these directly from our shared bus as
well.
We can get some of this from the initial power on of the device, I have a 2gs rigol which should be able to get the initial boot sequence. �;
We might also have to report a proxy sample set to the EMU so we have time to load up the samples into RAM. �New sd cards seem to be able to dump across a lot of info quickly, so we could also cheap out and play directly from the sdcard, though I don't think this is a good idea.
We may need an app to package these on the host side, doing things like mapping patches to samples, or ensuring samples get loaded in a specific order.
I like your idea about cheap PWM, it's actually a fun idea. �I was also thinking in terms of wavetable sweeps as well. �I guess we could use velocity as the key to trigger it, since most of the real processing happens after the ROM has dumped it's samples.
We should put together a google doc to start tracking this stuff.
On Sunday, July 13, 2014 5:39 AM, "janoch23@... [xl7]" wrote:
�
Don't get me wrong, I'd love dynamic sample loading. I was just saying that if it makes things less likely to happen at all than a regular flash rom, I'd prefer the latter. Otoh, if there is a bigger interest in a dynamic ram solution, then that would be more likely to happen.
In fact, if there's another CPU on the ROM module controlling RAM emulating flash rom, why not make it truly dynamic and modify the bytes on the fly for true PWM waves and supersaw :-) Seriously, naive rectangular PWM shouldn't be too impossible... Let's replace all the RAM chips with GHz FPGAs! :-o (no, please don't)
In fact, if there's another CPU on the ROM module controlling RAM emulating flash rom, why not make it truly dynamic and modify the bytes on the fly for true PWM waves and supersaw :-) Seriously, naive rectangular PWM shouldn't be too impossible... Let's replace all the RAM chips with GHz FPGAs! :-o (no, please don't)
Attachments
- No local attachments were found for this message.