Initiator Mode

Initiator Mode

What Is Initiator Mode?

“Initiator” is the SCSI term for a “Host Device”, or “The device which initiates communication on the SCSI bus”. For reference, “Target” is the SCSI term for a device like a Hard Drive, CD-ROM, Tape Drive, etc. A Target is the device which the Initiator is attempting to communicate with.

The Initiator can be a Mac, PC, Amiga, SCSI add-in card, etc. It can even be SCSI hard drives on occasion in later versions of SCSI.

Why is it useful?

This allows you to directly connect your compatible Desktop version (See Note above) BlueSCSI to a vintage SCSI drive and copy data from it without needing a bootable “Host Device”. So you can directly take a “Drive Image” so to speak, straight onto BlueSCSI. Significant changes were necessary to enable Initiator Mode, and it does not work with older hardware versions. It is not expected for Initiator Mode support to be added to other hardware styles due to the higher complexity and manufacturing cost.

Testing

Initiator Mode has been tested to copy data between BlueSCSI devices, and a few hard drives have been tested as well. Support for Tape Drives and other Targets is currently unknown, and would require test devices.

Instructions

• Initiator Mode requires BlueSCSI Ultra, BlueSCSI Ultra Wide, or a Desktop BlueSCSI version 2023.09a, 2023.10a, or later.
• Use the latest firmware.

Follow These Steps for BlueSCSI Ultra and Ultra Wide:

1. Install the SD card you would like to use for making backup images
2. Set the DIP switch labeled “Initiator Mode” to “ON” (this means the switch is closer to the words “Initiator Mode” on the PCB)
3. Ensure the PWR_ON jumper is installed
4. Connect your BlueSCSI to the Target device of your choosing (probably a hard drive), using any necessary SCSI connector adapters
5. NOTE: Remember termination considerations, both ends of the bus need to be terminated
   • Some Target devices can terminate the bus, but require Termination Power to do so
   • BlueSCSI Ultra and Ultra Wide can send power to the Termination Power line with the Back Feed jumper set
6. Power your Target with whatever setup is necessary (Old ATX power supplies are handy for this)
7. Apply Power to BlueSCSI
   • Power can be via USB-C or the Molex / Berg(floppy type) connectors on the BlueSCSI
     • If using USB-C, the power adapter needs to be able to supply at least 2 amps
   • BlueSCSI will now scan the bus for Targets
   • During Target scan, LED D6 will blink regularly
   • It can take some time to scan for Targets, especially older hard drives which take awhile to respond
   • You can connect a USB-C cable and open a Terminal to see realtime output.
8. When a Target device is discovered by BlueSCSI, the drive image process starts
   • LED D6 will blink more rapidly during data copy
   • Data transfer speed will vary substantially per Target device
9. After data copy is complete, LED D6 will blink slowly again and continue scanning the bus until power is removed
10. Assuming there is only one Target device on the bus (multiple are supported), after the fast blinking stops and slow blinking is seen again power can be removed at any time
    • If you have several Targets, it’s best to wait for at least 30 seconds of slow blinking before removing power from everything to ensure that BlueSCSI has started and completed the copy process across all Targets

Follow These Steps for BlueSCSI Desktop 50-pin:

1. On your SD card, create a file named bluescsi.ini with the following contents:

[SCSI]
InitiatorMode=1
EnableUSBMassStorage=0

2. Install the SD card into BlueSCSI
3. Move the jumper labeled Initiator and Target to the Initiator side
   
4. Install a jumper on the standalone Initiator jumper near a screw hole toward the middle of the board (by C21, C15)
   
5. Connect your BlueSCSI to the Target device of your choosing (probably a hard drive), using any necessary SCSI connector adapters
6. NOTE: Remember termination considerations, both ends of the bus need to be terminated
   • Some Target devices can terminate the bus, but require Termination Power to do so
   • BlueSCSI can send power to the Termination Power line with the Back Feed jumper set, when powered via the floppy power connector or USB-C (2023.09a only). 2023.10a can be powered via MicroUSB on the Pico.
   • BlueSCSI has a built-in terminator that can terminate one side of the bus, set TRM_ON by the SCSI connector
     
7. Power your Target with whatever setup is necessary (Old ATX power supplies are handy for this, as they usually also include a floppy power connector)
   
8. Apply Power to BlueSCSI
   • Power can be via USB power, SCSI Bus (if target device supplies TERM Power), or the Berg(floppy type) connector on the BlueSCSI
   • BlueSCSI will now scan the bus for Targets
   • During Target scan, the ACT LED will blink regularly
   • It can take some time to scan for Targets, especially older hard drives which take awhile to respond
   • You can connect a USB cable and open a Terminal to see realtime output.
9. When a Target device is discovered by BlueSCSI, the drive image process starts
   • The ACT LED will blink more rapidly during data copy
   • Testing has achieved up to 3 megabytes per second of transfer speed during data copy, but this will vary substantially per Target device
10. After data copy is complete, the ACT LED will blink slowly again and continue scanning the bus until power is removed
11. Assuming there is only one Target device on the bus (multiple are supported), after the fast blinking stops and slow blinking is seen again power can be removed at any time
    • If you have several Targets, it’s best to wait for at least 30 seconds of slow blinking before removing power from everything to ensure that BlueSCSI has started and completed the copy process across all Targets

After The Copy

On your SD card, there will be a new file named HDX0_imaged.hda, where X is the SCSI ID of your Target device. And the log.txt file will contain information about the drive’s capacity, sectors read, and an approximate read speed.

To use BlueSCSI as a Target again, the two jumpers must be moved back. Remove the standalone Initiator jumper and switch the other jumper back to the Target side.

Removable Devices

Removable devices such as CD’s or Zip disks will eject after imaging. New media can be inserted and will be imaged.

Adapters

Many times you may need to adapt the 50 pin SCSI cable to something that matches your target device:

• 40 to 50 pin SCSI adapter

What to do if sectors fail

As of the 2026.02.08 firmware release, there is a new INI file option to assist with sector transfer failures. BlueSCSI initiator mode normally just goes from sector 0 to the end of the drive when making a disk image. But there may be cases where you want or need to start at a specific sector when imaging a hard drive. This INI option allows you to start at a specified sector number.

In the INI file, use the option “InitiatorStartSector” to tell BlueSCSI which sector to start at on the specific SCSI ID of the target drive (this is in decimal notation, not hex).

[SCSI4]
InitiatorStartSector=57760

In this example, the target device is SCSI ID 4 and BlueSCSI will start at sector 57760 when imaging.
Note that this option does not overwrite any existing image files. It will make a new image file like usual and data will start at that point in the file. You will need to manually splice the data together into an output file.

Compatibility

Expect broad compatibility with SCSI Hard Disks. If you find one that doesn’t work please open an issue with a debug log.

Working

The following drives have been imaged with Initiator Mode successfully. Reports of successful drive imaging are appreciated.

• Bernoulli 150 External
• Conner CFA540S
• Conner CP2105S
• Conner CP30175E
• Conner CP3040A
• Digital RZ23 / Conner CP3100D
• Fujitsu M2513A6 640MB 3.5-inch Magneto Optical Drive (tested with 128MB and 230MB MO Disks)
• Fujitsu MCJ3230SS 2.3GB 3.5-inch Magneto Optical Drive (tested with 128MB and 230MB MO Disks)
• IBM 4GB OEM (Apple)
• IBM DPSS-309170 (SCSI-3)
• IBM Type DCHS
• Insite I325VM Floptical (tested with 1.44MB floppy)
• Iomega Jaz 2GB Model number V2000S (tested with 1GB Jaz disk)
• Iomega Zip 100 (Power the drive on after the BlueSCSI is powered)
• Iomega Zip 250 Model Number Z250S (We found we had to remove BlueSCSI termination and terminate the Zip drive for it to work)
• Maxtor 73455SR
• MiniScribe 20
• NEC CD-3010A CD-ROM Drive
• Plextor CD-RW Model PX-W4012TS
• Quantum CTS80S
• Quantum Fireball
• Quantum ProDrive
• Quantum XP34300
• SCSI2SD
• Seagate ST-1096N
• Seagate ST-12550N
• Seagate ST-1280N
• Seagate ST-138N
• Seagate ST-1480N
• Seagate ST-150176LC
• Seagate ST-157N
• Seagate ST-296N
• Seagate ST-32151N
• Seagate ST-3283N
• SyQuest EZ135S 135MB removable platter harddrive
• Toshiba MK2326FB 340MB 2.5” SCSI (40 pin, 2mm) harddrive

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