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Circuitbenders Forum => Circuitbending discussion => Drum machines => Topic started by: LoneStar81 on July 22, 2008, 05:58:36 PM

Title: Drum Machine OSes
Post by: LoneStar81 on July 22, 2008, 05:58:36 PM
Here are some OS ROM dumps of various machines:

http://lonestar.madtracker.net/OSpack.rar

Contents:
Alesis HR-16, HR-16:B
Kawai R-100
Korg DDD-1, DDD-5
Roland R-8
Yamaha RX5

Filenames contrain EPROM type (i.e. 27C256) and sometimes part name/number.
Viewing them you will notice that all on-display text is stored unencrypted and unscrambled. which makes personalising the OSes easy.
Title: Re: Drum Machine OSes
Post by: Gordonjcp on July 23, 2008, 11:06:32 AM
Viewing them you will notice that all on-display text is stored unencrypted and unscrambled. which makes personalising the OSes easy.

Not in the HR16 family, they're not!  The ROM is scrambled due to a hardware peculiarity which I've detailed in the past.  To descramble it, you need to grab and build svn://www.nekosynth.co.uk/nekosynth/utils/hr16utils/ to flip the lower eight bits of the address.
Title: Re: Drum Machine OSes
Post by: Circuitbenders on April 22, 2009, 06:08:27 PM
So i've taken a dump of the OS from a Kawai R-50 and edited the file so that in theory it should give a customised startup with different text on the screen. All i've done is find the text '*.KAWAI.R-50.*' and used a hex editor to change it to 'CIRCUITBENDERS' which convieniently has the same number of characters, and then resaved the .bin file. The problem i'm having is that i can't seem to write the new file to another chip as i get an error every time. The original file will write fine but the new one won't.

What am i doing wrong here?
Title: Re: Drum Machine OSes
Post by: Gordonjcp on April 22, 2009, 06:20:42 PM
Silly question, but have you blanked the chip?

Where do you get an error, in the EPROM programmer or on the drum machine?
Title: Re: Drum Machine OSes
Post by: Circuitbenders on April 22, 2009, 06:46:59 PM
I've tried it with a few 27C256 chips all of which were erased beforehand and all of which can be programmed with the original unedited OS file.

The error happens with the EPROM programmer. When you click program it more or less immediately comes up with 'Error at 0xD8' or something similar. If you read the chip back theres some stuff programmed but it looks to be garbage.

Should this actually work in theory? If you just alter the Hex values so the the Ascii output has different text should you be able to just resave it as a .bin file, burn it to a new EPROM and the drum machine will display the new text? I'm wondering if i've missed out some essential step like recompiling it or something.  :-\
Title: Re: Drum Machine OSes
Post by: Gordonjcp on April 22, 2009, 07:43:48 PM
That should be okay.  Either your EPROM programmer isn't configured properly or the EPROM is knackered, or incompletely erased.  It should read 0xff throughout when it's properly blank.
Title: Re: Drum Machine OSes
Post by: Circuitbenders on April 23, 2009, 10:50:39 AM
In a classic case of not seeing the wood for the trees i've worked out what the problem was. For some reason my programmer software just didn't like the fact that the filename of the edited bin file had brackets in it.

I just changed 'KAWAI_R50_OS_27C256-(CBstart)' to 'KAWAI_R50_OS_27C256-CBstart' and now it works fine.

(http://www.circuitbenders.co.uk/IMAGES/r50e/r50-cbstart.jpg)
Title: Re: Drum Machine OSes
Post by: Gordonjcp on April 23, 2009, 02:33:08 PM
Sweet!
Title: Re: Drum Machine OSes
Post by: sneakyalien on May 26, 2010, 03:03:51 AM
Hi,I read with interest your experiments with  drum machines and was wondering if in your opinion it is possible to remove the roms from the extra sound cartridges of an rx5 and read the data from them  using an Eprom blower,read the data into sound forge and then replace the data with new sounds and blow the new data to a new Eprom.This Eprom would then be placed back onto the circuit board of the cart and re-inserted into the RX5 giving it new sounds.
Is this possible or am I loosing the plot???
I have opened the cart up and it uses two mitsabishi chips
chip 1 is a M5M23C100-512P 645100
chip 2 is a M5M23C100-513P 643102
I understand the RX5 uses Yamaha AWM encoding,would this be a speacial weird unfathomable format or would it be raw binary.
Sorry for all the dumb ass questions,as you can tell I'm not very techy.
best regards.
Title: Re: Drum Machine OSes
Post by: Gordonjcp on May 26, 2010, 04:20:39 PM
Those will be JEDEC-format 1Mbit mask-programmed ROMs that could be replaced with EPROMs or flash memory.  Try 27C1000 for reading.
Title: Re: Drum Machine OSes
Post by: gretagrain on July 02, 2010, 09:35:16 AM
Is it possible to reburn the OS on a Roland R-8?
I have one that powers up but it looks like the os is fried...garbled display and no sound.

Any info is greatly appreciated.

Pete
Title: Re: Drum Machine OSes
Post by: LoneStar81 on October 01, 2010, 04:12:25 PM
Is it possible to reburn the OS on a Roland R-8?
I have one that powers up but it looks like the os is fried...garbled display and no sound.

Any info is greatly appreciated.

Pete

Sure, you just burn the OS dump on a new 27C010 aka 27C1001 (8bit x 128k, 1Mbit) eprom and you're set.
Title: Re: Drum Machine OSes
Post by: dJ dAb on January 07, 2012, 07:50:00 PM
Here are some OS ROM dumps of various machines:

http://lonestar.madtracker.net/OSpack.rar (http://lonestar.madtracker.net/OSpack.rar)

Contents:
Alesis HR-16, HR-16:B
Kawai R-100
Korg DDD-1, DDD-5
Roland R-8
Yamaha RX5

Filenames contrain EPROM type (i.e. 27C256) and sometimes part name/number.

Viewing them you will notice that all on-display text is stored unencrypted and unscrambled. which makes personalising the OSes easy.

I'll add my images shortly...
Drumulator
LinnDrum
Drumtraks
Oberheim DX
Title: Re: Drum Machine OSes
Post by: Glitch Militia on January 08, 2012, 08:02:12 PM
Anyone interested in Roland R-8 Mk.II ?
Title: Re: Drum Machine OSes
Post by: lazydog on November 04, 2012, 01:43:01 PM
the HR16 has a nice OS: i can't remember the button presses,
but you eventually get the name of the OS designer come up.
what a shame they didn't have that nice orange LCD on the
SR16 - which is essentially the same idea, updated.
Title: Re: Drum Machine OSes
Post by: aeldritch on May 16, 2013, 07:11:38 PM
Hi!
Someone will have the OS of casio RZ1?

Thanks!
Title: Re: Drum Machine OSes
Post by: iwillbeacircuitbender on September 09, 2015, 09:54:22 PM
Sorry, that is hard to find
Title: Re: Drum Machine OSes
Post by: SkinnyV on October 19, 2016, 08:36:00 PM
It's a bit late but it might be useful to the next person stumbling accross that thread in the future. I have started a small Synth EPROM dump repository because it seemed harder than it should to find stuff like that and I believe I have the firmware dump for the Casio RZ1.

You can find it among many other at : http://dbwbp.com/index.php/9-misc/37-synth-eprom-dumps

Thanks!
Title: Re: Drum Machine OSes
Post by: Circuitbender-needed-in-N on January 07, 2021, 07:53:06 PM
Looking for a circuit bender pro in NYC to modify a NES POWER GLOVE to a midi controller I dont know how to post here