Using the [BlueSCSI](https://github.com/erichelgeson/BlueSCSI) SCSI drive emulator and your compatible SCSI card, you have a fully internal hard drive with accessible microSD slot while still keeping your DB-25 connector free for other peripherals.
[](images/bluegs_v1.2_rear_installed_cropped.jpg)
[](images/bluegs_v1.2_rear_installed_right.jpg)
[](images/bluegs_v1.2_rear_installed_left.jpg)
# How it works
BlueGS connects between your SCSI card and its external DB-25 connector to give you a seamless installation. The BlueGS module itself mounts in a free DB-25 connector cutout in the rear of your IIgs or Enhanced //e.
[](images/bluegs_v1.2_installed_overhead.jpg)
[](images/bluegs_v1.2_installed_front.jpg)
# Features
* Gives your Apple IIgs or //e an internal, cable-free hard drive
* Can be powered from SCSI termination power only (if present)
* "Termination Power" mod is not required (when powered from the IIgs internal fan connector)
* Can *provide* termination power to the SCSI bus (when powered from the IIgs internal fan connector)
* Built-in termination that is controlled with a single switch
* TI/Unitrode termination ICs instead of passive termination, reduces power consumption by over 2/3rds
* [GGLabs A2SCSI](https://gglabs.us/node/2071) - a clone of the Apple Rev C SCSI card
Untested, but expected to be compatible:
* Apple Rev C SCSI and clones
* Apple High-Speed SCSI ("Sandwich II")
Unknown, but likely compatible:
* Ramfast SCSI
* Any SCSI card that uses has the same IDC-26/DB-25 pinout as the Apple Rev C SCSI
If you have an SCSI card with an IDC-26/DB-25 connector that has not been tested and would be willing to test your card with BlueGS, please [contact us](https://github.com/xunker/blue-gs/issues) to arrange to have a test unit sent to you.
# Performance
Using [BenchmarkD](https://www.brutaldeluxe.fr/products/apple2gs/benchmarked.html) with Apple IIgs (ROM 1, "Fast" speed), GS-RAM Plus w/ 2MB, GGLabs A2SCSI card.
Gerber files for v1.2 can be found in the [gerbers/v1.2](gerbers/v1.2) directory. **Note:** v1.2 has bugs and it not recommended for general use. V1.3 will be available shortly which will address these bugs.
This project would not be possible without the work done by [ztto](https://github.com/ztto/ArdSCSino-stm32), [Tambo](https://twitter.com/h_koma2), [Eric Helgeson](https://github.com/erichelgeson/BlueSCSI), and many others.
The "Blue Pill" footprint was originally created by [Yet-Another-Average-Joe](https://github.com/yet-another-average-joe/Kicad-STM32).
Symbol and footprint for Molex 105162-0001 MicroSD slot created by [SnapEDA user HMantz](https://www.snapeda.com/parts/105162-0001/Molex/view-part/).