|
|
@@ -1,33 +1,55 @@
|
|
|
SCSI2SD, The SCSI Hard Drive Emulator for retro computing.
|
|
|
|
|
|
+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
|
|
|
+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 ?)
|
|
|
|
|
|
-Traditional hard drives last X years. Maybe, if you're luckly, you'll get X 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 ofvintage
|
|
|
-computer hardware long after their mechanical drives fail. The use of SD memory cards
|
|
|
-solves the problem of transferring data between the retro computer and a
|
|
|
-modern PC (who still has access to a working floppy drive ?)
|
|
|
-
|
|
|
-Features:
|
|
|
- Terminator, termpwr, firmware upgradable (via the SD card)
|
|
|
- Selectable SCSI ID (via jumpers)
|
|
|
- Emulates a non-removable hard drive (does not present as a removable memory card reader) for maximum compatibility.
|
|
|
- Unit attention configurability.
|
|
|
-
|
|
|
-Technical Specifications:
|
|
|
-SCSI Interface: SCSI-2 Narrow 8-bit 50-pin connector.
|
|
|
-SD Card Support:
|
|
|
- (state max size)
|
|
|
- Currently SD standard (1GB), no SDHC/SDXC support.
|
|
|
-Power:
|
|
|
-Dimensions:
|
|
|
-
|
|
|
-Performance:
|
|
|
-Sequential read/write: 250kb/sec, 50kb/sec. Add some results of some SCSI hard drives
|
|
|
-for comparison. 160Mb, 250Mb, 1Gb.
|
|
|
-
|
|
|
-Compatibility:
|
|
|
-Tested with Linux, Apple Macintosh System 7.5 on LC-II, LC-III, and LC-475 hardware.
|
|
|
-Love to hear your success stories on other platforms.
|
|
|
+*All statistics are made up.
|
|
|
|
|
|
|
|
|
+Features
|
|
|
+
|
|
|
+ In-built active terminator.
|
|
|
+ Can optional supply terminator power back to the SCSI bus
|
|
|
+ Emulates a non-removable hard drive for maximum compatibility.
|
|
|
+ Firmware updatable over USB (TODO software not yet implemented)
|
|
|
+ Highly configurable over USB (TODO software not yet implemented)
|
|
|
+ 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)
|
|
|
+
|
|
|
+
|
|
|
+Technical Specifications
|
|
|
+
|
|
|
+SCSI Interface
|
|
|
+ SCSI-2 Narrow 8-bit 50-pin connector. Supports asynchronous transfers only.
|
|
|
+SD Card Interface
|
|
|
+ Standard SDSC (1GB maximum size)
|
|
|
+ SDHC (32GB maximum size)
|
|
|
+ SDXC cards are untested. Donations welcome.
|
|
|
+ Communication is via the SPI protocol at 25MHz.
|
|
|
+Power
|
|
|
+ 5V via standard molex drive connector.
|
|
|
+Dimensions
|
|
|
+ 10cm x 10cm x 1.5cm
|
|
|
+ A 3D-printable bracket is in testing to suit a standard 3.5" hard disk bay.
|
|
|
+
|
|
|
+
|
|
|
+Performance
|
|
|
+
|
|
|
+As currently implemented:
|
|
|
+Sequential read: 250kb/sec Sequential write: 50kb/sec
|
|
|
+
|
|
|
+These numbers are dreadful. I am working on updating the slow polling SD card
|
|
|
+communication to use DMA. I expect the performance to reach 1.8Mb/sec.
|
|
|
+
|
|
|
+
|
|
|
+Compatibility
|
|
|
+
|
|
|
+Tested with Linux (current), Apple Macintosh System 7.5.3 on LC-III, and LC-475
|
|
|
+hardware.
|
|
|
+
|
Michael McMaster