Roland Quick Disk Emulation
- At August 08, 2019
- By amsynths
- In Sampler
15

Overview The Quick Disk drive in the early Roland samplers is prone to failure and long since obsolete. One of my background projects is to create an micro processor emulator, as I have 3 of these samplers. This post details progress to this goal.
How the data is stored Each side of a QD contains one bank of 64k bytes of data which contains sample data, wave parameters and the performance parameters and split points. When a QD disk is loaded it moves the sample data as 12-bits into DRAM wave memory and replaces the current 8-bit wave and performance parameter values in the SRAM chip with the new ones. However you can choose to just load the sample and wave data and not the 26 performance parameters, if you want to keep the original settings. You can also preview the name of the sample before loading the disk.
Variations The S-220 introduced the capability to store more parameters as it introduced new capabilities beyond the S-10 and MKS100. The S-220 OS recognizes three types of sample disk:
- Type I – S-220 All Information (F2 pushed during save)
- Type II – S-220 Basic Information
- Type III – S-10 or MKS-100
The different amount of parameter data does not affect how the QD works or is emulated.
Sample Memory The wave memory is built from six HM50464P 64kx4 bit DRAM chips, which provides 128k of 12-bit sample storage in total. Because this data is stored in 8 bit bytes on the QD the 12-bit sample data is stored as 2 complements in 2x 8 bit words onto the disk. A disk side therefore contains 64k bytes of sample data and up to 8k bytes of wave and performance data (which is held in a 64k bit SRAM backed up by the battery). The 29 items of wave data control how the sample is played back; loop points, envelope settings, auto bend etc.
The limitations of the QD storage size means Roland had to split the sample memory into 4 banks, with each bank requiring a single side of a QD. So a full memory load means 2 disks and 4 load operations. Each side of a QD can hold 64k bytes, which is split into …
The samples are replayed via a 16-bit DAC at 15 or 30 kHz, which provides 2.18 seconds or 1.09 seconds of sample time per bank. This is remarkable short compared with today’s software sampling but it is the same wave memory size the Emulator 1 used in 1981 at a cost of $10k.
The sample bank can have a name which is 9 alphabetical characters which is stored as two hex characters.
Use Cases The QD in the Roland S-10, MKS-100 and S-220 has only a few use cases;
- There is no formatting of the disk, as it has no sectors.
- Full Read – reads the complete sample bank
- Monitor Read – reads just the sample bank name and structure
- Full Write – writes the complete sample bank
- Verified Write – checks whether there is sample data or its an empty disk then writes the complete sample bank
Essentially the QD needs to do only 3 things; partial read, full read or full write. Partial read is controlled by the OS and is not a QD function.
QD Interface The interface to the QD consists of 10 lines:
- /WRITE PROTECT – indicates whether the disk is write protected or not
- /WRITE DATA – data is written here when WRITE GATE is high
- WRITE GATE – enables recording
- /MOTOR ON – Low sets the disk motor running
- READ DATA – read data stream
- /READY – reading or writing can take place
- /MEDIA SW – indicates disk is inserted or not
- /RESET set low for reset period after POWER ON RESET
- +5V
- GND
The read and write hand shaking is very basic and described in the Roland services notes. The QD uses standard MFM encoding (its a DD disk!) and has a clock rate of 101 kHz much lower than the DS/DD floppy drive clock of 250 kHz.
Gotek Flash Floppy Solution Originally I was going to make my own ARM chip based emulation, but after seeing how the Gotek floppy emulator can be loaded with a completely new and flexible code set, I ditched my plans. There are three challenges:
- The clock rate is lower and not an integer, however the FF code can be configured to run at different clock speeds.
- The QD has no software sectors or notion of indexes and steps across tracks. Its just one track. This can be configured as simple 64kb FTE.
- The hand shaking and I/O pins are a bit different to a floppy. Once again this can be configurable in the code and mapped in cabling.
I/O Mapping Lets take a look of how the 10-pin QD connector maps to a standard Shugart floppy 34 pin connector.
A QD Solution Jean-françois Del Nero is the developer behind a Gotek HxC firmware update that supports Quick Disks, details are here. Kief Fraser is the developer behind Flash Floppy and he is also working on a version as well and the wiki is here.
In mid August a version of the HxC code was announced that supports Quick Disk and I have tested this out on a Roland S-220. The Gotek drive casing is 2 mm wider than the QD drive and 2 mm smaller in height. I took 1 mm off each side of the drive using a craft knife and then designed a PCB that attaches to the base of the drive and to the QD metal mounting bracket, so the drive is at exactly the right place. The PCB is 150 x 120 mm and contain a JST 10 pin connector for the cable to the Roland main board, a 34-pin IDC connector to attach the drive to, along with 4-pin power.
The original 10-pin grey connector on the QD is close to being a JST connector, but it needs a little bit of work with a craft knife to smooth the sides so it fits.
Setup Instructions I reprogrammed the Gotek drive with the commercial HxC firmware (£10) as my drive was programmed with Flash Floppy when I bought it, which does not work with the QD software. The Gotek USB stick is formatted in FAT32 on Windows and has a copy of the latest QD firmware saved on to it as a .UPD file.
The drive is powered on with both buttons depressed and it reads the software and updates the firmware perfectly. The index configuration file should be used, along with blank QD file renamed to DSKAxxxx.QD. Files can now be selected on the Gotek and the file number is correctly displayed on the 3-digit LED.
23 August First test completed but unfortunately it did not work. I checked all the cabling and no errors. A Load fails with “Illegal Disk” message on the S-220, which we expect as the sampler cant read an empty disk. However the Save function does not work as the data verification fails in the S-220 after the write and then read. I have sent a copy of the QD file to Jean-francois, so he can diagnose the issue.
18 September Success! The HxC emulation of the Roland QD drive works perfectly! I have upgraded the Gotek with a nice blue OLED display, so you can see the Sample Bank name and loaded the Roland Factory sample banks onto the USB drive. The latest V3.4.1.7 HxC firmware can be downloaded here.
The file names can be extended by appending text after the basic DSKAnnnn format, and I have used Bank Letter followed by Bank Name (e.g. A Bass Drum). The OLED display scrolls the text across the screen, so the window in the plastic casing does not need to be enlarged to see all the text.
Jeff
Hello,
It seems you are mixing 2 different projects and 2 different peoples in your post :)). The only one currently supporting QuickDisk on Gotek is the HxC Firmware for Gotek v3.4.1.4a. Have you tested my Gotek HxC firmware supporting the QuickDisk finally ? Let me know ! 🙂
Alejandro Abadía
I will try with flash floppy 3.13a alpha. In theory this firmware is able to read and write quick disk from an to a ald roland sampler
Ian
Hi
I have original songs recorded using Roland PR100 & MT32 many years ago. It seems that either the PR100 is now faulty as the disks won’t load, or the disks themselves are. I have no way of knowing which scenario is correct. Is there any way to get back the data straight from the 2.8 QD format without using the PR100?
Many thanks
Ian
amsynths
Look for a working quick disk drive and then record the midi out into a software sequencer. I may have a working quick disk drive if you need one.
Darren Saunders
Hello I have a Roland W30 with usb instead of the floppy drive. I have been looking at buying a usb loaded with samples for Roland S10, S20, S220, MKS-100 and MT-100. I have asked the seller if the samples work on the W30. He doesn’t know at all but his does know the samples are in .qd format.
Do you know if .qd works with my W30?
amsynths
Hi, only S220, MKS100 and S10 can read .qd sample files. I have all the factory S10 samples in Gotek format which I will load up in my Manuals section. REOb
Junkmale
Hi,
I can’t get this to work with my S10. I played some email tennis with Jean Francois but jumper settings etc did not help yet. Did you make it work with an S10?
Matthew Robinson
Hi Amsynths,
How did you convert the sample library to Gotek format?
I have everything up and running on my S-10 and can save samples (although still confused about the USB menu, I assume i am saving it to the blank QD file?)
I have the samples downloaded as Sysex and wav. and cannot find the workaround to load them on to USB to be read.
Any help would be greatly appreciated.
amsynths
I created 100 blank qd images on the usb stick using the right naming convention.
Then I loaded the S10 with a sample bank by sysex and saved to the Gotek, sample bank by sample bank.
I can send you a usb stick with all the Roland sample banks, if that helps.
Matthew Robinson
Thanks for the fast reply. I now understand from your comment that I need a qd image for each sample.
I would gladly pay you for a USB, your time and postage.
Thanks again,
Matt R
amsynths
I will create a new USB image over Xmas..and let you know when its done. Rob
Voikimov
Nice info thanks a lot .
GDog
Hey create write up!! I too would be interested in getting the S10 sample pack set in Gotek format. Really appreciate it
amsynths
Hi
The factory sample banks in Gotek format are here:
https://www.dropbox.com/s/ruvco8edkftfa4j/Roland%20S10%20L100%20-%20L111%20QD%20Images.zip?dl=0
Best Regards
Rob
Daniel
Hi,
I noticed you had a similar issue to mine, in that you got the verify error when trying to save. Your later update suggests you were able to remedy this issue? I have this issue with my S10. Loads QD images with no issues, but when I try to save, I get the verify error. I’ve got the 3.5.2.5a QD firmware installed. Curious how you were able to successfully save. Thanks!