SCSI2SD: Difference between revisions

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(Michael moved page SCSI2SD to SCSI2SD old: This page is now for historical reference only, and does not necessarily describe the device as-built.)
 
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#REDIRECT [[SCSI2SD old]]
<p><strong>The SCSI Hard Drive Emulator for retro computing.</strong></p>
 
== News ==
<p>
<strong>10 Sep 2013:</strong><br />
It works!
I have a working prototype that works well. There are a few minor errors in the PCB layout that will be fixed in the next revision.
</p>
 
== Overview ==
Traditional hard drives last 5 years<sup>*</sup>. 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 ?)
 
<sup>*</sup>All statistics are made up.
 
== Features ==
# In-built active terminator, enabled by a jumper.
# Can optional supply terminator power back to the SCSI bus
# Selectable SCSI ID
# Emulates a non-removable hard drive for maximum compatibility.
 
== Technical Specifications ==
{|border="1px"
|SCSI Interface
|SCSI-2 Narrow 8-bit 50-pin connector. Supports asynchronous transfers only.
|-
|SD Card Interface
|Standard SDSC (1GB maximum size)<br />
SDHC (32GB maximum size)<br />
SDXC cards are untested. Donations welcome.<br />
Communication is via the SPI protocol at 25MHz.
|-
|Power
|5V via standard molex drive connector.
|-
|Dimensions
|10cm x 10cm x 1.5cm
|}
 
== 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.
 
== Howto ==
* [[FormatWithBasiliskII]] Format an SD card for use with Apple Macintosh hardware using the [http://basilisk.cebix.net/ Basilisk II] emulator
== Old ==
 
For historical project information see [[SCSI2SD old]]

Revision as of 12:53, 10 September 2013

The SCSI Hard Drive Emulator for retro computing.

News

10 Sep 2013:
It works! I have a working prototype that works well. There are a few minor errors in the PCB layout that will be fixed in the next revision.

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 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.

Features

  1. In-built active terminator, enabled by a jumper.
  2. Can optional supply terminator power back to the SCSI bus
  3. Selectable SCSI ID
  4. Emulates a non-removable hard drive for maximum compatibility.

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

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.

Howto

Old

For historical project information see SCSI2SD old