SCSI2SD
The SCSI Hard Drive Emulator for retro computing.
Download
- downloads for v3/v4/v5 hardware revisions.
- downloads for v6 hardware revisions. This firmware will NOT work on the older boards.
News
[7 October 2016]v6.0.13 Bugfix release
- Added glitch filter to SCSI signals
- Restored parity-checking option (defaults to disabled)
[12 September 2016]v6.0.10 Bugfix release
- Fixed issue with some UHS-1 SD cards.
- Fixed SCSI corruption issues
[27 August 2016]v6.0.8 Synchronous transfers
- Fixed "SCSI2SD config protocol error" when saving config settings to the SD card.
- Fixed USB storage with 3 or more devices configured
- Added support for synchronous transfers up to 10MB/s
[14 August 2016]v6.0.6 Performance improvements
- Fixed performance bugs, especially for write performance. Sync transfers coming soon...
[14 August 2016]v6.0.5 First non-BETA V6 firmware
- Fixed more SCSI bugs. The firmware should work on most systems now, excluding an issue on some Amiga machines.
- Added firmware update support to scsi2sd-util6. See the updated Quickstart guide for instructions.
[16 July 2016]v6.0-BETA3 Fixed V6 firmware
- Fixed critical SCSI bug. There was a silly bug that prevented the previous v6 firmwares from working on most systems.
Apologies for the delay in finally fixing this bug and getting the firmware stable. The v6 boards will leave BETA status now as soon as
the scsi2sd-util6 utility supports firmware updates on all platforms. Performance improvements (ie. 10MB/s synchronous support) will be done after firmware upgrade is fixed.
Early adopters should update the firmware using dfu-util on Linux or STM DfuSe on Windows. Remember to put a shunt on the pins labelled "BOOTLDR" and reconnect the USB cable to enter bootloader mode.
[16 June 2016]v6.0-BETA2 New V6 firmware
- Fixed SD card compatibility issues
- Fixed SCSI compatibility issues
- Added SD card hotswap support
- Performance improvements
[17 May 2016] Sneak-peak at the new V6 boards
SCSI2SD V6 will go on sale from 28th May with BETA quality firmware. This is a completely new hardware design which adds commonly requested features.
The V5 boards will remain available for the foreseeable future. Most people should continue to buy the older V5 board ! The V6 boards are more expensive to produce, and most people don't require the additional functionality.
- Full-Size SD slot. This makes it much easier to develop faceplates for external access. I am currently prototyping a matching 3.5" bracket with faceplate.
- A floppy-style berg power connector is used instead of the traditional Molex plug. This reduces the width of the device, simplifying 3.5" bracket production. Most systems can self-power the board and don't need a separate power cable anyway.
- Better performance. The hardware supports synchronous transfers at 10MB/s.
- Access to the data via USB. The SCSI2SD drives will appear when connected to a PC via USB. This is limited to around 1.2MB/s (USB FS speeds).
- Superior noise resistance to deal with poor termination and poor cabling.
- Integrated terminator, now enabled via software configuration
Initial BETA firmware limitations:
- No hot-swap support
- Inconsistent performance due to immature firmware. The boards may not perform any better than the V5 boards until the software is improved to make use of the faster hardware.
- Cost and supply limitations. I only have a small number (50) of V6 boards available in the first batch, and priced at $125 AUD.
[12 January 2016]v4.6 New firmware
- Fixed bug when using sector size that isn't a multiple of 4 (eg. 522 bytes)
- Fixed a bug that caused hanging or scsi phase errors on high speed scsi hosts.
- Fixed a hang when processing a SCSI RESET in a data phase.
- scsi2sd-util: Fixed USB connection problems under Windows 10.
- Added option to treat luns as separate devices
- Improved boot up time. It is now possible to replace the bootloader with a version that doesn't pause for 2 seconds (bootloader). This is required on some Amigas and the Staubli JC5. Replacing the bootloader CAN BRICK YOUR DEVICE if it fails half-way, so do not attempt this unless necessary.
Overview
Traditional hard drives last 5 years*. Maybe, if you're luckly, you'll get 10 years of service from a particular drive. The lubricants wear out, the spindles rust. SCSI2SD is a modern replacement for failed drives. It allows the use of vintage computer hardware long after their mechanical drives fail. The use of micro-SD memory cards solves the problem of transferring data between the vintage computer and a modern PC (who still has access to a working floppy drive ?)
*All statistics are made up.
Purchase
The new V6 board and 2.5" PowerBook version are available at:
- codesrc.com (Australia)
The 3.5" boards are available from the following distributors:
- itead (China)
- Inertial Computing (USA)
- AmigaKit (UK)
3rd party accessories
- durhamcardco.com Internal faceplates for V5 and V6 boards, and external V5 case.
- Thingiverse nibblernibbles has created a 3d-printable external enclosure for the SCSI2SD + DB25 adapter. Power can be supplied over USB for hosts which don't supply termination power.
- SCSI2SD V5 & V6 Bracket by Maya Designs
Features
- In-built active terminator.
- Emulates up to 4 SCSI devices (7 for the V6 version)
- Supports sector sizes from 64 bytes to 8192 bytes
- Firmware updatable over USB
- Highly configurable over USB
- Selectable SCSI ID
- Selectable parity support
- Enable/disable Unit Attention Condition
- Artificial limits on the SCSI disk size (eg. limit size to 4G to avoid OS bugs)
- Sector size (can also be set via the SCSI MODE SELECT command, as sent by SCSI format utilities).
- External LED connector.
Technical Specifications
| V5 hardware | V6 hardware | |
| SCSI Interface | SCSI-2 Narrow 8-bit 50-pin connector.
Supports asynchronous transfers only. |
SCSI-2 Narrow 8-bit 50-pin connector.
FAST10 (10MB/s) synchronous transfers. Higher speeds to be supported with firmware update. |
| SD Card Interface | microSD, tested up to 64GB Communication is via the SPI protocol at 25MHz (3MB/s theoretical max) |
Full-size SD, tested up to 32GB Up to 20MB/s |
| USB Interface | Firmware updates and configuration
USB 2.0 micro-B |
Firmware updates, configuration, and mass-storage
USB 2.0 micro-B. Mass-storage at USB 2.0 FS speeds (1.2MB/s max) |
| Power | 5V via standard Molex 4-pin drive connector, USB, or self-powered using the SCSI host termination power.
2.35W maximum (500mA) DO NOT CONNECT 12V at all if you need to make your own power cable as it risks destroying the board if you accidentally swap the wires. |
5V via floppy 4-pin drive connector, USB, or self-powered using the SCSI host termination power.
2.35W maximum (500mA) |
| Dimensions (L x W x H) | 5cm x 10cm x 1.5cm | 10cm x 9cm x 1.5cm |
| Performance
Tested under optimal conditions. For comparison, here are some benchmarks of some older SCSI hardware. |
Up to 2.6MB/s read, 2.3MB/s write. | Up to 10MB/s. |
Compatibility
Files
Firmware update utility and configuration tool at:
These files are currently available for Windows, Linux, and Mac OSX.
A copy of all sources can be obtained via the command:
git clone --recursive git://www.codesrc.com/git/SCSI2SD
or (for V6)
git clone --recursive git://www.codesrc.com/git/SCSI2SD-V6
Alternatively, the git sources can be viewed using your web browser by clicking here or here (V6)
Howto
- SCSI2SD FAQ
- SCSI2SD UserManual
- FormatWithBasiliskII Format an SD card for use with Apple Macintosh hardware using the Basilisk II emulator
Alternative Open SCSI Projects
- AJ's alternative implementation. AJ and I originally had a competition to design and build a SCSI device to boot an old Mac LCIII. The deadline for that competition has long-since expired without a winner, but we have both continued to progress our designs.
- S2I (was: SCSI2IDE)
- AVR based SCSI RAM disk
Old
For historical project information see SCSI2SD old
