eharmon

2023-07-04 — updated 2023-10-04

There are a few ways to get a classic Macintosh online. Here I focus on my personal systems, the SE and SE/30. However, this guide largely applies to the Plus as well.

A fantastic, extremely complete guide has been done by Mk.558, this page serves as a shorter reference to finding and setting up the basic hardware in common configurations. I highly recommend reading the complete guide to learn the full ins-and-outs of classic networking.

Easiest, But Very Rare (SCSI-to-Ethernet)

The single simplest solution is obtaining an extremely rare SCSI-to-Ethernet adapter. These came in a number of common models:

Generally, these are universal and support most Macs with SCSI from their era of release.

As far as I know, all SCSI-to-Ethernet adapters made can provide standard RJ45 at 10Mbps, meaning they’re generally compatible with modern network hardware including switches and routers. The only exception I’ve heard of is the original Dayna SCSI/Link (DP0800)1.

Some of these can be powered from an ADB passthrough cable, but this can push the bus hard, so using a power adapter is likely preferable.

All of these should work with an SE or SE/30 except the Asante Micro EN/SC, as I believe it has a male HDI-30 connector and I’m not aware of any female HDI-30 to DB25 connectors.

For many of these units, any 25W 12v DC adapter outputting 800mA may work. Ensure you are using center positive.2 However, always double check your device as incompatible adapters can cause serious damage.

The Pocket SCSI/Link uses 5v, and I’ve successfully used a 5W 5v DC adapter outputting 1A, with center positive. Do not use 12v with this device.

Drivers

Drivers are always required for SCSI-to-Ethernet adapters, the Macintosh OS does not ship with native compatibility.

You can find most of them on Vintage Apple’s Driver Museum mirror.

For Dayna adapters I recommend using version 7.7.2.

Manuals

Setup

These devices are very nearly plug-and-play. If you don’t have a manual, these generic steps might help:

  1. Turn everything off.
  2. For devices with a selectable SCSI ID, ensure it is set to something not already in use. Typically this might be something like 4. This will be a physical switch/dial.
  3. Set termination as needed, if the device has this setting. If this is the only device plugged into the external SCSI port, enable termination. This will also be a physical switch/dial.
  4. Plug the DB25 cable into your Macintosh. Some devices will use a DB25 to DB25 (same on both ends), and some will use a DB25 to HDI-30. Regardless, for a desktop Mac the DB25 end needs to connect to the Macintosh with the other end plugged into the adapter.
  5. Plug in the ethernet cable.
  6. Plug in the ethernet adapter to power.
  7. Turn on your Macintosh.
  8. Install the drivers.

Easy and Common (PiSCSI)

The second easiest way to get your system online, and by far the most common is with a PiSCSI and a Raspberry Pi, which as of this update (July 2023) are finally coming back in stock. This is relatively inexpensive as even a Pi 3 offers reasonable performance and the PiSCSI is fairly cheap. All-in you’ll be looking at less than $100.

This should be compatible with any SCSI-supporting Macs which can use the Dayna driver.

If you’re not prepared to solder, this can be as simple as buying a pre-assembled PiSCSI, connecting it to your Rapsberry Pi’s GPIO header, copying the PiSCSI image to an SD card, and going through setup.

PiSCSI has excellent documentation, but as it’s a very capable device it can be a bit overwhelming. If you’re already familiar with Raspberry Pi and Linux, I recommend:

  1. Copy the latest release image to your SD card.
  2. Follow the connection instructions. You don’t have to continue to Drive Setup instructions if you don’t need any hard disks.
  3. Follow the ethernet setup instructions. As above, I recommend the Dayna 7.7.2 driver listed on the Driver Museum mirror.

Since the PiSCSI documentation is a wiki, these links might go stale. If they do, you can try the main wiki page.

Easy and Never Worth It (Serial-to-Ethernet)

It’s possible to bridge between the serial ports and Ethernet with a variety of peripherals. These cost money and are dog slow, so I’ve never bothered to experiment, and I recommend the same. If you want networking and you’re gonna spend a few bucks, go for something with more utility.

Hard, Rare, and Fast (PDS Cards)

The hardest, and fairly rare (but not as rare as the SCSI-to-Ethernet solutions) method is to install an Ethernet card into your PDS slot. This has a few advantages:

Unlike the SCSI-to-Ethernet adapters or a PiSCSI, these are not universal. Early Macs have no PDS slots, and SE and SE/30s use different slots. Be careful to select a device which matches your Macintosh. Additionally, some adapters come without 10BaseT or AAUI connectors (Thick or Thin Ethernet-only). You are unlikely to have any hardware which supports these, so they are to be avoided.

Extremely non-exhaustive list for SE:

Extremely non-exhaustive list for SE/30:

Setup

I highly recommend following the setup guides for the individual cards, however, these generic steps might help:

  1. First, a warning: High voltages are present in monitors and power supplies, including those in old Macs. These can be EXTREMELY dangerous and cause injury or DEATH. Maintenance should only be performed by a trained electronics professional. Macintosh systems are not intended to be user servicable. If you do not have the required expertise seek a professional to perform this maintenance. The following is provided as a rough guide for professional technicians only and is not a guide to installing any specific hardware.
  2. Turn everything off.
  3. Unplug the Macintosh.
  4. Safely disassemble the Macintosh according to the official technician documentation to gain access to the PDS slot.
  5. Insert the card into the PDS slot.
  6. Remove the expansion slot cover from the rear panel.
  7. Install the daughter board into the rear panel.
  8. Connect the daughter board to the PDS card.
  9. Safely reassumble the Macintosh according ot the official technician documentation.
  10. Turn on the Macintosh.
  11. Install the drivers, if needed.

Software

Once your hardware is setup, you’ll want to complete the software configuration. I recommend following the PiSCSI guide in all cases, as it is non-specific:

PiSCSI Macintosh Setup Instructions

  1. Herb’s Stuff ↩︎

  2. Apple Rescue of Denver ↩︎