ATARI HDD Drive ACSI EmulatorACSI hard drive emulator for ATARI ST, STF, STFM, STE, MEGA ST, original project acsi2stm by Jean-Matthieu COULON.In our products we use only original processors STM, from authorized sellers and high-quality DB-19 connector with mounting screws. The case is high-quality 3D printed using PETG material.Main featuresMount 3 standard SD/SDHC/SDXC cards on the Atari (FAT16/FAT32/ExFAT).Expose raw SD cards as ACSI hard disks connected to the Atari.Expose ACSI hard disk image files as hard disks connected to the Atari.It also provides an UltraSatan compatible real-time clock if you add a simple 3V lithium battery such as a CR2032.Power the unit via its USB Type-C port. It has no specific power requirements, so any 5V USB Type-A to Type-C cable (or PC) should be able to power the unit.Power supplies with the Power Delivery (PD) protocol are not supported.ModesOffer access to SD cards formatted with FAT16, FAT32, or ExFAT. No additional drivers need, making it easy to transfer files between your Atari and modern PCs. GemDrive Mode
Emulates traditional ACSI hard drives and supports multiple partitions. This mode requires Atari-compatible hard disk drivers, offering enhanced compatibility with legacy software. ACSI Mode
Hardware compatibilityACSI2STM was successfully tested on the following configurations:
Atari 520 STF, TOS 1.04, GemDrive + ICD driverAtari 520 STE, TOS 1.60, GemDrive + ICD driverAtari 1040 STE, TOS 1.62, GemDrive + ICD driverAtari 1040 STE, TOS 1.62, GemDrive + PP driverAtari 1040 STE, TOS 2.06, GemDrive + Atari AHDI driverAtari 1040 STE, TOS 2.06, GemDrive + ICD driverAtari 1040 STE, EmuTOS, EmuTOS integrated ACSI driver + GemDriveAtari Mega STE, TOS 2.06, GemDrive + Atari AHDI driverAtari TT030, ACSI mode (driver not specified)GemDrive mode is currently tested on Atari ST and STE (no TT or Falcon). It probably works on the TT or the Falcon. If anybody owns this hardware and is interested, please open a GitHub issue. Testing is safe for the hardware, not for data.TOS >= 1.04 (“rainbow TOS”) is strongly recommended because older TOS will leak a small amount of memory when a program stops. It may or may not have an impact depending on how you use the machine.TOS replacements such as MultiTOS, MiNT or others are incompatible with GemDrive mode. Implementing multitasking in GemDrive is nearly impossible on such a small microcontroller.
SD card, partition and file system compatibilityACSI2STM is compatible with all SD cards that can work in SPI mode, meaning most old SD cards, all SDHC and all SDXC cards. New SDUC was not tested and probably won’t work, but who needs more than 2TB on a ST ?In GemDrive mode, the SD card must be formatted either in FAT16, FAT32 or ExFAT format, with a single partition (the standard format for SD cards). The partition size is limited to 2TB.In ACSI mode, the SD card must be formatted with Atari tools. TOS restrictions apply.In ACSI image mode, the SD card must be formatted with standard SD format (like GemDrive) and the image itself must be formatted with Atari tools.Floppy disk images in ST format can be used as ACSI images and will appear as a small C drive on the ST. This won’t make games compatible though since it is not a real floppy emulator.
Emulator compatibilityACSI images are compatible with Hatari ACSI images. Using a SD writing tool like Raspberry Pi Imager, you can transfer an image to the physical SD card.GemDrive cards are mostly compatible with Hatari’s GEMDOS drives, with a few differences in unicode translation, long file name support or other details.Other emulators provide similar features but were not tested.
Atari software compatibilityThis section explains why some programs are compatible and some are not.
Software properly using the operating systemThese programs use the normal GEMDOS interface to access disk drives. This means that they have no path restrictions and follow the rules.
Programs usually working like this:
Most desktop programsA few games with no disk protectionBasically everything using the standard file selector to open files
Compatible with
Internal floppy disk (A:)External floppy disk (B:)ACSI hard diskGemDriveHatari GEMDOSSoftware relying on bugsThese programs use the normal GEMDOS interface to access disk drives but rely on weird patterns or buggy TOS error codes to work properly.
Compatible with
Internal floppy disk (A:)External floppy disk (B:)ACSI hard diskGemDrive
Incompatible with
Hatari GEMDOSSoftware doing BIOS accessThese programs access low level disks using BIOS or XBIOS interfaces.
For full manual visit RETRO-SPEKTRO site
LOT - 1pcsATARI HDD Drive ACSI Emulator with case.
ATTENTION - ATARI 520STe, microSD cards, USB Type-C cable, battery CR2032 not included !!!If you buy more than 1 of my item, I will do combined shipping and reduce the shipping cost.
Every device is fully tested on original hardware before shipping and carefully packed.Retro computers and vintage peripherals are over 30–40 years old. Correct operation of accessories depends on the condition of the original computer.If you have any questions or experience any difficulty after receiving your order, please contact me first. I am always happy to help with installation, setup or troubleshooting.Thank you for your purchase and for supporting classic computing!
IMPORTANT INFORMATIONInternational shipments may require additional time due to customs inspection or local postal processing. Delivery times are outside the seller's control.Tracking is provided and will remain active until delivery. In some cases, tracking updates may be delayed while the item is being processed by customs or the local carrier.If you have any questions about your shipment, please feel free to contact us before opening a case.
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ALL ITEMS ARE WELL PACKED TO AVOID DAMAGE DURING SHIPPING.ALL GOODS ARE SHIPPED BY REGISTERED MAIL WITH A TRACKING NUMBER.