DSP4000 Upgraded To 4500

[siegfriedmeier]

Hey all!

Just acquired one of these and was hoping it could be further expanded.  There is an H3000 Legacy bank, but it doesn’t have all the excellent patches such as Magic Air and Micropitchshift from the H3000.  Is there a way to add any more banks and presets to these?

Just wondering on what our options are to maximize this unit.

Thanks!

Sig

Attachments:

You must be logged in to view attached files.

[andrejr]

Hi Siegfried! I just got a DSP4000 that I hope to fix, and I’m really interested in upgrading it now that I have it apart and am messing with it.

Where and how did you get a 4000 upgraded to 4500? Did you have it upgraded yourself or by a tech? I’d love to get in touch with someone who could give me the dumps of the EPROMs for the 4500 so I could do such an upgrade on mine, I have an EPROM burner. I’d, of course, pay for the images. I think the 4500 has a lot more presets (and hence EPROMs) than the DSP4000, so I’d need dumps of all of them. Do you maybe have a pic of the insides of the device?

Thank you very much!

[italoop]

Andrej

there is no such thing as an upgrade for the DSP4000 to DSP4500. There was a PCMCIA “Alchemy 101” Card coming with Eproms V2.300 that added the last collection of Vsig modules and presets to a 4000, developed for the 4500.

Also, the 4500 came standard with a sampler board which the 4000 didn’t have. So a 4000 “upgraded” to 4500 would require sampler card + Alchemy Card + V2.300 EPROMs.

Another VERY important detail is that the 4500 didn’t have EPROMS as it was the first Eventide using flash memory… so things get almost impossible.

[andrejr]

I guess that when we talk about upgrades, there’s the System Rom aspect (which dictates which models are available in Vsig), and there’s the presets aspect.

I have the worst DSP4000 variant, the v1, it has fewer EPROMs for presets than any other (v1 presets) + v1 system ROM. What I’d like to get is the latest system ROM, to get the modules (particularly interested in dither, I want to use it to emulate old stuff like SPX90 Symphonic), and I want to get as many presets as I can. So, by your words and what I’ve read online elsewhere, the “stock” way would be to get the v2.300 EPROM and that’s it, + cards.

As for the presets, I’d first have to get the DSP4000 v2 preset EPROMs (b/c I don’t have them and they’re stock on newer DSP4000s), and get the “Alchemy 101” card. But from what I’ve read online, the 4500 also has all the Broadcast presets (also available on card, and in the 4000B variant) + some 200 more presets, maybe another card, I forget. Not sure if those 200 presets include the sampler stuff I don’t really need. So to get those I’d have to be switching cards during use, which is annoying (and I got an SRAM card w/ my device which I plan to use for my own stuff).

But there’s another aspect, I’m a (lapsed, switched to regular programming) embedded engineer, and have some reverse engineering experience (embedded and otherwise). The DSP4000 uses chips from 2 pretty vanilla families, Motorola DSP56k and m68k, former being the DSP. Both have readily available disassemblers, assemblers, compilers even, that run on modern PCs (even in Linux, which I use). The DSP is ironically irrelevant here, it just chews on whatever the CPU gives it through the “host interface”. The m68k CPU is what runs the system Rom, reads the preset ROMs, does I/O, … And “gives” the DSP code to the DSP chips.

If I get all the images of the flash chips from a DSP4500 (or even a sysex dump of an update or whatever, if that’s the complete software minus the bootloader), I can figure out if their memory layouts are any different from the EPROMs I read from my device, maybe adjust them a bit if needed and make the presets work from burned EPROMs. The whole thing is unlikely to be much different, I doubt they switched the packaging approach. If there’s stuff that needs to be changed in the system ROM to get it to read the new chips, that’s unlikely to be hard. I can figure all the addresses from the physical PCB layout of the address lines and what they connect to, m68k datasheets are widely available. I can likely remove presets that use the sampler if that poses an issue.

The goal here is not to really port all the DSP4500 code. That’s also likely doable but a bit more work to “jump over” all the 4500-only stuff + likely there are issues supporting v1 DSP4000 hardware. The goal is to port all the presets, and most importantly, burn them into EPROMs so I don’t have to switch cards. I hope I’ll find the 2.300 for the actual System ROM, and then get that to work w/ ported presets. I could also likely read them from cards and turn them into EPROMs, but the 4500 seems like the largest collection in one place.

The whole thing sounds fun to do and with a good cause, and totally doable because it’s all vanilla chips, unlike Lexicons w/ Lexichips and the proprietary Ensoniq chips. Hell, I think even those have vanilla CPUs, now that I think about it.

BTW there’s precedent on reversing Eventide stuff, like getting the H3000 series to properly work with cheap modern OLED screens: https://huebnerie.de/2019/09/eventide-h3000-h3500-oled-update/

[Author]

Posts