The presumably most important differences between the latest SCSI2Pi release and PiSCSI 26.08.01 are listed below.
| Feature | SCSI2Pi | PiSCSI | Remark |
|---|---|---|---|
| SCSI2Pi 7.0: Support for the Raspberry Pi 5 | ✅ | ❌ | SCSI2Pi supports the Pi 5 (target mode and initiator mode), with a choice of hardware or software handshaking |
| Support for many Raspberry Pi OS versions | ✅ | ❌ | SCSI2Pi supports Raspberry Pi OS Bullseye, Bookworm and Trixie, all 32/64-bit. Distributions like Ubuntu and Manjaro should also work. |
| Quick installation with Debian binary packages for Bullseye, Bookworm and Trixie | ✅ | ❌ | Installation, uninstallation and update of releases and development versions for all Pis in just a single step, including on Bullseye and Bookworm |
| Support (e.g. for development and testing) also for many other platforms | ✅ | ❌ | SCSI2Pi also compiles on PC Linux, OpenBSD, FreeBSD, NetBSD, macOS, or MSYS2. Tools such as s2pctl can even be run on some of these platforms. |
| Low memory footprint | ✅ | ❌ | The SCSI2Pi binaries are significantly smaller (in some cases by more than 40%) than those of PiSCSI. Less memory is also required at runtime. All of this is particularly important for "small" Pis. |
| Up to 25% higher transfer rates | ✅ | ❌ | Measured with a Pi Zero WH (25%) and a Pi 4 (5%) |
| Support for the GAMERNIUM board | ❌ | ✅ | This old board only offers comparatively slow transfer rates, but makes maintaining and optimizing the code more difficult. SCSI2Pi has been optimized for STANDARD and FULLSPEC boards. |
| scsiloop tool | ❌ | ✅ | To test your board, simply use the scsiloop tool from the PiSCSI distribution |
| scsimon tool | ❌ | ✅ | Removed because a lot of data is lost, which is misleading during analysis |
| Block devices as image files | ✅ | ❌ | This feature makes it easy to exchange data with other devices using USB storage media |
| SCSI-to-USB bridge | ✅ | ❌ | USB mass storage devices can be used like SCSI mass storage devices |
| Professional streamer (tape drive) support | ✅ | ❌ | With tar files or standardized SIMH files as images, support for filemarks, navigation, variable block sizes, and more |
| Backup/Restore of real tapes | ✅ | ❌ | Conversion of tapes into SIMH-compatible image files and vice versa |
| Booting VMS from an emulated tape drive | ✅ | ❌ | Made possible thanks to support for SIMH tape image files |
| Variable sector sizes for hard drives | ✅ | ❌ | In multiples of 4, for exotic platforms |
| Linked SCSI command support | ✅ | ❌ | Improves the compatibility with some platforms |
| Configuration files and properties | ✅ | ❌ | Convenient configuring of all settings without a command line |
| BlueSCSI/ZuluSCSI compatibility mode | ✅ | ❌ | Support for the BlueSCSI/ZuluSCSI filename conventions for images |
| Configurable caching modes | ✅ | ❌ | An optional write-through cache ensures consistent image files |
| Configurable and additional mode pages | ✅ | ❌ | User-definable mode pages for optimal driver/platform compatibility |
| Cloning of drive properties | ✅ | ❌ | It is possible to clone not only drives or tapes but also the mode pages, ensuring the emulation corresponds as closely as possible to the original |
| New and improved initiator mode tools | ✅ | ❌ | With the FULLSPEC board: New and improved tools for hard drives and streamers, higher compatibility with the SCSI standard |
| Virtual bus (in-process bus) with tools | ✅ | ❌ | With the virtual bus and s2ptool, s2p can execute SCSI commands without any board hardware, particularly for testing purposes |
| Scripting of SCSI commands (recording/replaying) | ✅ | ❌ | s2pctl and s2pexec can execute SCSI command scripts generated by s2p |
| API for management with SCSI commands | ✅ | ❌ | The connected computer can control s2p with SCSI commands |
| Improved and extended logging | ✅ | ❌ | Improved error analysis capabilities, configurable logging of payload data |
| Tool for formatting media with USB drives | ✅ | ❌ | E.g. for USB floppy disk drives, runs on any Linux system |
| Tool for analyzing and creating tape images | ✅ | ❌ | Supports SIMH-compatible tape image files, runs on Linux/BSD/macOS |
| Tool for sending SCSI commands | ✅ | ❌ | Sends any SCSI command to any physical device |
| Tools for advanced testing | ✅ | ❌ | Testing of SCSI commands on Linux/BSD/macOS |
| SCSI2Pi 7.0: Support for integration tests | ✅ | ❌ | In addition to unit tests, with s2p_test -i or make integration |
| Optional compilation of device types | ✅ | ❌ | Faster compilation and even smaller binaries, if not all device types are needed |
| Additional functions for the SCSI Control App | ✅ | ❌ | SCSI Control offers additional features, e.g. notifications when s2p reports errors |
Several PiSCSI tickets that have been open for a long time, or that have been closed without being processed, have been addressed for SCSI2Pi.
| PiSCSI Ticket | Remark |
|---|---|
| 335 | Improved caching, optional write-through cache |
| 479 | Improved support for the SCSI commands READ/WRITE LONG |
| 480 | Streamer support for VMS, support for SIMH tape image files |
| 497 | SCSI-to-USB bridge |
| 1226 | Raspberry Pi 5 support |
| 1402, 1410, 1412 | DEC Alpha compatibility |