I am going to attempt to dump the ROM chips this weekend with my LA and hope that it works. I may have to abort though as I suspect the cheap chip pin hooks I got may be to big for this to work.
Ok, I have managed to connect to the data bus on the wave ROM with my IC clips. I have attached the Sigrok PulseView files to this post as I was not able to get them properly converted to a sensible hex value. I have one file that may be under sampled and one that is over sampled. I could not match the 10Mhz clock rate of the synth.
The problem is that every data point gets converted into a hex value because of the way it is sampled so there can be multiple of the same hex values for the read.
I have confirmed that my old 80's EEPROM programmer does not support the suspected MX23C6410 / MX23C8100 chip that is for both the ROM chips.
I have found that I may be able to use my Sanni cart reader (https://github.com/sanni/cartreader) with an and adapter board (SNES Maskrom Flash adapter https://github.com/sanni/cartreader/wiki/Flas … adapter-for-hw3) and a SOP44 to DIP44 adapter to properly dump the wave ROM. I have already ordered the SOP44 to DIP44 adapter.
@Falcosoft I have done some more testing and have found that just removing the Sysex F0411042124024063066F7 from the deadend MIDI file also makes it play correctly with out the loud instruments. Not sure if that narrows down any issue or not. I also tried another non Sound Blaster 16 (CT1740) sound card (a ESS AudioDrive ES1868F) to see if the issue with the dead end file was sound card related and it was not.
The reason why I swapped out the sound card is because my Sound Blaster 16 has the version 4.11 chip on it which I have read has MIDI issues.
I have swapped back to the Sound Blaster 16 as it seems to make the computer run faster and I had a blue screen when installing the joystick virtual driver for the ESS sound card.
Poot36 wrote on 2025-03-22, 23:31:@Falcosoft I have done some more testing and have found that just removing the Sysex F0411042124024063066F7 from the deadend MIDI file also makes it play correctly with out the loud instruments. Not sure if that narrows down any issue or not. I also tried another non Sound Blaster 16 (CT1740) sound card (a ESS AudioDrive ES1868F) to see if the issue with the dead end file was sound card related and it was not.
The reason why I swapped out the sound card is because my Sound Blaster 16 has the version 4.11 chip on it which I have read has MIDI issues.
Hi,
1. The conclusion stays the same as before. This SysEx modifies some modulation LFO parameters on channel 4.
2. No sound card can cause such an issue. Sound card specific Midi related problems are more like hanging notes, Midi slowdown etc.
That is good to know.
I have another file that does not play quite correctly but no loud instruments, it is ADVENT.MID.
I have attached it and a recording of it to this post. I had to reduce the bit rate a bit on this one and make it variable as it was over the 5Mb limit.
Some of the instruments sound odd or off is all I can describe it as.
Poot36 wrote on 2025-03-23, 01:15:That is good to know. I have another file that does not play quite correctly but no loud instruments, it is ADVENT.MID. I have […]
That is good to know.
I have another file that does not play quite correctly but no loud instruments, it is ADVENT.MID.
I have attached it and a recording of it to this post. I had to reduce the bit rate a bit on this one and make it variable as it was over the 5Mb limit.
Some of the instruments sound odd or off is all I can describe it as.
This time I do not see any obviously suspicious Midi messages so first you should try to identify the problematic channel(s). You can use Midi player for this. On the right hand side of the player you can find the Channel selector and the Mute button. You should mute the channels one by one until the problematic sound stops. My first tip is channel 6 Program 88 (Fantasia).
Ok, I have done some testing and for some reason channel 6 Program 88 is listed on my setup as New Age Syn Pad. Is it possible I have the MIDI player program set up wrong and that could be part of the issue? I also found that if I increase the volume in the MIDI player software I can hear more instruments playing for some reason.
I also found out that my home made 1/4" to 3.5mm headphone adapter was starting to fail so I suspect my previous recording my not have been as correct as it should be.
Poot36 wrote on 2025-03-23, 23:06:Ok, I have done some testing and for some reason channel 6 Program 88 is listed on my setup as New Age Syn Pad. Is it possible I have the MIDI player program set up wrong and that could be part of the issue? I also found that if I increase the volume in the MIDI player software I can hear more instruments playing for some reason.
I also found out that my home made 1/4" to 3.5mm headphone adapter was starting to fail so I suspect my previous recording my not have been as correct as it should be.
No, it's not a serious problem. New Age Syn Pad is just the GM name of the same istrument. But of course you can set Midi Player to display the GS name but it does not change the sound:
BTW, you should play back the Midi file at maximum volume since it seems lower than max. volume can result in problems on your synth.
I will have to figure out a headphone attenuation solution then as this synth goes quite loud with high efficiency headphones. It could also be the large dynamic range could be the issue as well.
I wonder if I could bypass the amp in the synth and that may also fix the slight hiss when no sound is playing as well.
Well I finally got in the parts to attempt to dump the ROM's however there is an issue.
I found that my programmer does not know what the ID of the ROM's is so it won't attempt to dump it.
The ID type 1 is 526F and the ID type 2 is 526C. I think this is manufactures ID and the part ID but I could be wrong about that.
I am not smart with coding so prehaps someone who is could modify the code to allow me to dump the chips?
The code is here: https://github.com/sanni/cartreader/releases/tag/V13.1
I will try upgrading to the latest version and see if that helps but I doubt it.
Well it looks like upgrading to the latest portable version (14.3) allowed me to dump the chip.
I did try dumping the waverom as a 2Mb chip as I thought it may be a bigger chip then was stated in the service manual but it is not.
So there is duplicate data in the dump.
I have attached the dump to this post.
Maybe someone can figure out what other Roland products this matches.
I have also just managed to dump the CPU ROM chip as well.
I have double dumped it as well as I was not sure how the chip worked in 8 bit mode when it in the circuit is wired for 16 bit mode.
This may not be a correct dump so it may not work as expected.
I have attached it to this post.
(NOTE: this dump is confirmed to be a corrupted dump do not use!!!)
I think this decompiler may work with the CPU that this unit runs but I can not be sure.
The name is dasmh85.exe and for some reason I can not get it to run on my system.
I have attached it to this post.
Well I have been able to confirm that my CPU ROM dump was corrupt as I attempted to dump it again and this time the chip ID was different.
I have found out also that the ROM is byte swapped so I have attached the original correct dump and the byte swapped one to this post.
The ROM is still doubled up though.
Well browsing through the ROM I found a string stating GS Standard VER=2.00. I assume this means that it supports that standard?
As discussed before, the EM-10 is a SC-50 more or less, so yes, it's a basic GS synth.
@Spikey Thanks for the conformation.
I found this text in the ROM: EM50 EM30 EM20 EM10 SOFTWARE STAFF: * Ferrari Luigi * --- * Marrucci Massimiliano * --- * Ricci Giorgio * --- * Sbaffoni Manrico * --- * Cameli Piero * --- * Giacomozzi Mariano * --- * Colo Enrico * --- * Completamente bolliti
Not sure if it is seen at any time by the user or not.
