Dear ViperSan,

I do also a lot of archiving with KF and created recently https://wiki.retronn.de
It is still in a very early state and currently mainly focused on C64 originals. We have a small team with experts on C64 copy protection mechanism that are able to create G64 images from one or often more KF streams that have a correct representation of the protection included. So these G64 images are the closest to the original image containing the protection and also run in emulators.

So while the imaging is only the first step the verification, testing and further analysis is very very time consuming.

I have not seen public libraries attempting archiving to such extend. Even if they have an archive of the original cardbox boxes the information on the media slowly decays. We often need nowadays several streams from different originals to recover the whole relevant information.

So best regards and greetings to a fellow archiver *thumbsup*.

elianda wrote on 2019-07-31, 17:58:

Dear ViperSan,

I do also a lot of archiving with KF and created recently https://wiki.retronn.de

Hi Elianda,
I recently found your site after searching for any music software that would work with some MusicData MIDI-related cartridges my dad had bought for our c64 back in the 80's.

One is a MIDI interface cartridge, while the other is described as a MIDI Synchronizer though its connector is for the user port.

I've never really understood what the latter cartridge was for, though googling online now, there was a mention that MusicData had a MIDI sequencer software package and so I guess it related specifically to that.

I noticed that MusicData's MIDI sequencer was archived on your retronn.de site, but seems to require a password to download it.

https://wiki.retronn.de/index.php?title=Music … _Midi_Sequencer

I tried making an account there on the wiki, but that username/password didn't seem sufficient.

I found your site mentioned in this thread so thought I'd try give you a ping here to see if you'd be able to help me out.

Regards,
Gurce

Hello Gurce,

I sent you a private message with more info.

elianda wrote on 2024-03-10, 23:20:

Hello Gurce,

I sent you a private message with more info.

Hi Elianda,

Thank you for the private msg and your assistance there. I was unable to respond in private msg (don't have enough access here yet due to newbie status), so will reply here.

I dropped a few more photos of the two carts here, along with photos of the top and bottom of their pcb's, hope it's helpful 😀

Regards,
Gurce

https://gurce.net/c64_files/musicdata_carts/

Thank you for the photos, I will forward them to the community and we will see what we can make of it. In case you find the manual of it, feel free to give me a note.

I would also be interested to hear if you get the sequencer software working with the cartridge.

I've been trying the past two nights. Found it challenging to transfer the g64 file across to a floppy. I haven't tried the star commander route you suggested, as I was worried I might need to get an older Windows/dos OS to run it, but if you reckon there's a way to get it working in modern windows, I can look further into it.

The alternate pathway I tried was using my Ultimate-II cartridge, which seems to be happy to mount g64 images. I tried setting the ultimate-ii to unit 9, and my 1571-drive as unit 8. I tried using the cart's ulticopy tool to copy from u9 to u8, but it spat out errors.

So I tried using an Action-Replay .crt to perform a 'whole-disk' copy from u9 to u8, this seemed to work ok-ish. With the newly written floppy in my 1571 and the midi cartridge inserted, I tried loading this MusicData MIDI Sequencer. Sometimes it would load, other times it would fail to load.

On the times I got a successful load, I tried to record something (with my piano's MIDI-OUT hooked to the cart's MIDI-IN). I tried my best to fathom the UI (based on the 'H' help). Think I did the following:
- Pressed F1 to highlight in red the "1" item in the 'RC' column (I assumed 'RC' stood for record on a particular channel)

- I then pressed 'RETURN' for what I assumed equated to 'START RECORDING'

- I tried pressing some keys on the piano, didn't get much signs on the c64 screen whether this was received or not
- I pressed 'SPACE' for what seemed to stop the recording session (this seemed to also unhighlight the red "1" item in 'RC' column)

- I pressed 'RETURN' again, for what I thought would equate to playback (I swapped my MIDI cable to be piano's MIDI-IN hooked to cart's MIDI-OUT), but unfortunately, no music played back.

Just to share the backstory of cart purchase and how it came about. My dad would follow the computer magazines of the day and read about the MIDI-craze hitting the home computer market, so was trying to find a way for his kids to experience it on their C64. He went from suburb to suburb, visiting music stores and asking about possible options for the c64. Most of them didn't cater for it and were encouraging him to buy an Atari ST instead.

He eventually found one music store in the city, the guy there had something in stock, I don't think he knew a great deal about it, from memory, I think he also offered to throw in that synchronizer cart for free too, so dad took the deal.

I'm not sure if it came bundled with instructions or software, I suspect not.

I recall dad trying to find us different music software, to try figure out what would and wouldn't work with this cart. I recall it being a very "hit and miss" experience. Many things didn't seem to work, but once in a while, we'd bump into things that would.

The best luck we ever had with it was with a program he bought called "Advanced Music System". When setting this software to PASSPORT mode, we were able to get the cart's MIDI OUT to talk to the piano's MIDI IN. I recently tried this option out via my MEGA65 and recorded that in this vid:
- https://www.youtube.com/watch?v=HVCvC1pCr8I

This 'Advanced Music System' also purported to offer a means to record MIDI from your piano too, but back then, it never seemed to work. I tried it in the mega65 vid too, still didn't work.

So yeah, that's how my current journey came about, after discovering these carts while doing some house-cleaning, I thought I'd give them another chance and see if I can have more success with them in some way.

I've also ordered a TeensyROM cart, that has MIDI functionality, and it should arrive in a week or so, I'm curious to see how it performs in comparison to this MusicData cart.

Tonight I thought I'd do some extra investigation into the cartridge. I'll upload a video of some of my experiences tonight with:

Video Link: https://youtu.be/NqprQ4BC0eA

Summary of Highlights:

Using the MIDI cart with 'Advanced Music System'
- interestingly, the MIDI OUT from the cart (to my piano) ran into issues if the MIDI IN was also connected to the cart
- I later observed that MIDI OUT playing worked fine when the cart's MIDI IN was disconnected

Using MusicData MIDI Sequencer
- Not much luck with it
- Did notice 'something' gets recorded, but maybe it's garbage
- Upon trying to play it back, it doesn't seem to play any notes, but if I hold piano keys down, I can sometimes hear pitch bend events, or it switches between instruments
- I also noticed that if the MusicData Synchronizer cart is plugged in, it seems to permit me to switch the SYNC setting between OUT and IN (via the 'T' key)

Additional studies:

I thought I'd also try decipher the components inside the cartridge, to try get a feel for how it works, maybe it might reveal some clues if something is amiss.

I've uploaded all the related datasheets here:
- https://gurce.net/c64_files/musicdata_carts/datasheets/

Here's my attempt to annotate the top-view and bottom-view of the cart with the pin/signal names that I could figure out. My hope is that maybe I could figure out a schematic for this cart, based on what can be observed here, and that might help out with debugging it more deeper in future.

Top View

Bottom View

Ok, the past few nights, I've been incrementally trying to build up a schematic, still not complete yet (maybe 60% 85% done, and might have mistakes), but sharing what I have so far in-case it's insightful.

I'll try flesh this out some more in the days ahead. Ok, have refined it some more the following day.

One other observation I had while checking continuity on the 3 DIN plugs, I noticed:
- The MIDI IN only has two pins connected (I guess that middle pin is just some earth/shield thing, so maybe not critical
- MIDI OUT1 pins seem fine (this is the working port afterall)
- MIDI OUT2 pins seem to be in the wrong positions (on the outermost pins, instead of the pins adjacent to the middle shield pin)

So this might explain why I never got MIDI OUT2 working in the past (or perhaps MIDI OUT2 had some other unique, special purpose that I'm not familiar with).

I've fleshed out more of the schematic a bit more (updated it in the prior post).

Taking a look at the MIDI IN lines (red and black) and what they tie up to, they do look a little odd to my eyes. I would have thought they ought to pass through the anode + cathode lines, but instead, they both seem to be tied to the anode in some odd way. I had another inspection of the pcb the next day, and indeed the cathode is connected, and the circuitry here seems ok.

Given this, it might explain why MIDI IN on this cart never worked 😁

Reflecting on the gotchyas I've encountered so far, it makes me imagine that in these early days of MIDI in the 1980's, these new companies forming to come into the MIDI scene (such as MusicData) were new, small operations, perhaps working from their garage or home office, manually soldering up the components and wiring for each cartridge, and probably didn't do a great deal of manual testing to confirm it all worked. That might explain some of the "hit-and-miss" nature of what some end-users were experiencing... 😀

Anyways, over time, I will try to get familiar with the components on-board, and get a better feel for what the circuit was trying to accomplish, where it went wrong, and maybe how it could be remedied.

I was curious as to who MusicData were, as they seem to have a pretty low profile online. I found this in an old "Musician" magazine from 1984, which shed some light:

Hmm, so they speak mainly of selling their gear via mail-order only, so maybe again highlighting the small-scale nature of the company, rather than pushing more heavily to music retail stores.

The article does a bit of name-dropping, so I could potentially try and chase up the mentioned musicians and see if they have any memory of who MusicData were:

Jeff Baxter
https://www.jeffskunkbaxter.com/

Ray Manzarek
https://en.wikipedia.org/wiki/Ray_Manzarek

Denny Seiwell
https://en.wikipedia.org/wiki/Denny_Seiwell

So, Jeff is a Guitarist, Ray was a keyboardist, Denny is a drummer... Hmm, given that, could they have been directly involved, and a part of the MusicData company? I could try give one of them a ping to find out 😀

Due to such limited mention of their company name over the years, I'm suspecting that the company didn't stick around for long and perhaps folded after a year or two. Feel like they were trying to accomplish a lot, on multiple platforms (Apple, C64 and other), with efforts in both hardware and software, maybe they over-stretched themselves.

Taking a look at their address, 8444 Wilshire Blvd Beverly Hills California, It seems like this small hole-in-the-wall shop, so feels like it must've been a pretty small operation.

Taking a look at the side-view of the awning, this is indeed 8444:

Ah ok, another potential penny is dropping for me, after a friend Terry Raymond mentioned that his Datel MIDI cart (made in Germany) had problems running on his C64, as he is in the USA with an NTSC c64, and he suspected a clock issue.

When I reflect on my situation, maybe I'm in the reverse case. I am in Australia with a PAL C64, but an NTSC MIDI cartridge.

Since a lot of the circuitry in the schematic is making use of that phi2 signal, so googling online for the difference in CPU clock frequencies, I see:
- PAL: 985,248 Hz
- NTSC: 1,022,727 Hz

Hmm, given that, maybe the divisor used by the timers will impact the final resulting clock used for the serial comms. MIDI appears to need 31.25 kbps.

Anyways, will try get better acquainted with the programmable timer in the circuit over time, and understand how it is performing this division, and if there's any means to tweak that division...

UPDATE:
- Taking a look at the HD6350 serial chip, I see it has a programmable divisor of either /16 or /64. I assume /16 divisor was chosen for this.
- I see that the phi2 clock went through the flip-flop which ought to halve the clock.
- So for NTSC, the comms clock would be: 1,022,727 Hz / 2 / 16 = 31.96 kHz
- So for PAL, the comms clock would be: 985,248 / 2 / 16 = 30.79 kHz

Hmm, so neither of them would be 'exactly' MIDI's 31.25 kbps. While there's probably some leighway/tolerance for clocks to be 'slightly' off, I'm suspecting that the NTSC clock is within that threshold, and maybe the PAL clock is slightly out.

So maybe there might not be much hope of getting the clock any closer given what's there. Maybe one option could be that I could try post my MusicData cart to Terry in the US, and if he's up for it, he could try post his Datel cart to me in Australia, and we could try each other's carts on our C64s! 😁

Hmm, another possibility on my mind. If indeed clock speed is the issue, maybe I could try add a little extra circuitry to provide a pure 1MHz crystal/oscillator, and feed that into the flip-flop (rather than the phi2 signal).

It would mean cutting the connection between the flip-flop and the phi2 signal and replacing it with my external 1MHz oscillator...

No guarantees that this will solve the problem of course, but anyways, just an idea in the back of my head... 😀

Finally, some good news, I got to the bottom of the issue with MIDI IN on this cartridge! 😀 I noticed there was a pull-up resistor on the OUTPUT signal from the optocoupler that had one leg that wasn't soldered down.

After I soldered it down, it made all the difference! 😀

I captured this video of the journey, to savour the moment of victory! 😁

- https://www.youtube.com/watch?v=EjLtJqa-2T0

thanks for keeping updates here, you can see from the number of thread views that there have been some following along 😀

Hehe glad you folks enjoyed the journey too 😀

I guess there are a few remaining mysteries that I could keep investigating (exploring the synchronizer cart, and figure out what's going on with MIDI OUT2), but will probably take a rest from it after tonight's win, and come back to it another time 😀

Just a little update on my confusion on the MIDI OUT2 pinout of my MusicData cart:

I was recently reading the documentation of another MIDI cartridge by Passport Designs, and that doc hinted at a port related to drum machines.

Reading more online about this kind of connection, it is referred to as "DIN-SYNC":
- https://en.wikipedia.org/wiki/DIN_sync

> DIN sync was introduced in 1980 by Roland Corporation with the release of the TR-808 drum machine.[citation needed] The intended use was the synchronization of music sequencers, drum machines, arpeggiators and similar devices. It was superseded by MIDI in the mid-to-late 1980s.

The pinout on wikipedia indicates that more signals were added over time for other duties (fill-in, reset-start):

Ok, so looks like my OUT2 was intended to be connected to a pre-MIDI drum machine (like a Roland TR-808 drum machine) with the intention of sending start/stop signals to it, and adjusting its tempo. Judging from my latest schematic, I think the red/green lines were as follows:

So taking a look at a Roland TR-808 drum machine online (don't think I'll buy one of these, a bit too pricey for my liking 😁), yeah, looks like they had a DIN socket on the back for this 😀