This page addresses some frequent questions and provides tips related to storage devices connected to the Atari. Note that some of this information applies to the current version of HDDRIVER only.

Installation and Partitioning
Do I lose any data when switching to HDDRIVER from another driver?
No, all existing data remain unchanged when installing HDDRIVER. Drives with partitions created by very old versions of the ICD driver software, which was using a non-standard partitioning scheme, require a special treament. In this case data have to be converted with software that is included in the HDDRIVER distribution. No data are lost by this conversion.
When installing HDDRIVER another already installed hard disk driver will automatically be disabled.
Are the partitions created by HDDRUTIL compatible with other drivers?
Yes, the partitioning scheme created by HDDRUTIL is fully AHDI compatible. This is not only the case for pure TOS compatible partitions, but also for TOS/Windows compatible partitions. Pure Windows compatible partitions are compatible with all platforms/drivers which support Windows compatible partitions.
Do I need to re-configure HDDRIVER after installing a new version?
No, when installing HDDRIVER the settings of the currently installed version version are automatically applied, provided it is not older than HDDRIVER 7.93. If this is not possible HDDRUTIL displays a respective message.
How much RAM does HDDRIVER need?
The amount of memory required by hard disk drivers for the Atari solely depends on the size of the biggest partition, the cache settings and the settings for removable media. Configured for minimum memory usage and with small partitions HDDRIVER allocates less than 28 KiB RAM.
HDDRUTIL requires 1 MiB of RAM.
What is the maximum drive/memory card capacity supported by HDDRIVER?
HDDRIVER supports devices and memory cards of any capacity. Drives > 2 TiB cannot be used by TOS, MagiC or MiNT with their full capacity, though, because these systems only support 32 bit sector numbers. Tools like HDDRUTIL or DISKUS, which support 64 bit sector numbers, can access sectors beyond the 2 TiB limit by using the SCSI Driver integrated in HDDRIVER. In order to use the full capacity of media > 1 GiB with the ACSI bus a suitable host adapter (ICD compatible) or a suitable memory card adapter (GigaFile or UltraSatan) is required.
What is the maximum partition size supported by HDDRIVER?
The maximum partition size in the first place depends on the operating system and on the filesystem. TOS 1.00/1.02 support partitions of up to 256 MiB, TOS 1.04-3.06 of up to 512 MiB, TOS 4.0x of up to 1 GiB, MagiC of up to 2 GiB. These sizes are also valid for boot partitions and TOS/Windows compatible partitions. With Big-DOS the TOS limits can be lifted. MiNT and MagiC support filesystems (FAT32/ext2) that do not have any relevant size limit.
How many drives/partitions does HDDRIVER support?
All TOS versions support up to 16 BIOS drives (A:-P:). With HDDRIVER partitions can also be assigned to the drives A: and B:. With MagiC HDDRIVER supports up to 25 partitions (A:-Z: except U:), with MiNT or Big-DOS up to 31 partitions (A:-Z: except U: and 1:-6:).
Do drives/memory cards have to be formatted before partitioning?
No, formatting is only required for drives/memory cards with bad sectors.
Does HDDRIVER belong into the AUTO folder?
No, because HDDRUTIL installs HDDRIVER as HDDRIVER.SYS in the root directory of the boot partition selected during the driver installation.
Only software emulators, where the system is not booted from a drive image but from a emulated GEMDOS drive, require HDDRIVER.PRG in the AUTO folder of this drive.
Does HDDRIVER require AUTO folder programs like FOLDRxxx, CACHExxx or SCSIDRV?
No, with HDDRIVER these programs are not needed. HDDRIVER can be configured with the respective settings instead.
Hardware Support
Does HDDRIVER support memory cards?
Yes, memory cards are fully supported by HDDRIVER. They are ideal for exchanging data with other platforms, and they are inexpensive and noiseless alternatives to hard disk drives.
Note that for memory cards the HDDRIVER settings for removable media are relevant.
Does HDDRIVER support Atari SH and Megafile drives?
Yes, all drives of the SH and Megafile series are supported.
Does HDDRIVER support any SCSI drive?
Any Single Ended SCSI drive (but no LVD SCSI drives) can be used with the TT's or Falcon's SCSI bus. Drives with a bus width of 16 bit (e.g drives with an SCA connector) require a customary adapter that reduces the bus width to 8 bit.
Which hardware supports drives/memory cards > 1 GiB connected to the ACSI bus?
SCSI drives > 1 GiB connected to the ACSI bus require special hardware in order to make use of the full drive capacity. Suitable hardware are the adapters by Inventronik, the GigaFile, the UltraSatan, the ICD Link and the LINK96/97. (This list may not be complete.)
HDDRIVER does not detect a SCSI drive connected to the ST/STE.
ST and STE do not have a real SCSI bus but only Atari's proprietary ACSI bus. Certain devices (those that require the so-called initiator identification) connected to this bus can only be used with the LINK96/97 host adapters or the adapters by Inventronik. Additionally, when using other adapters it may be required to switch off the drive's parity checking.
Does HDDRIVER support SATA devices?
Yes, with a standard IDE-to-SATA adapter SATA hard disk drives/SSDs or SATA DVD/BD drives can be can be used with HDDRIVER.
Does HDDRIVER support IDE or SATA devices connected to the SCSI bus?
Yes, with an Acard AEC-7720U SCSI-to-IDE bridge IDE and SATA (with an additional IDE-to-SATA adapter) drives have been successfully used with the SCSI bus and HDDRIVER. How well this works may vary depending on the particular drive and adapter, though.
Does HDDRIVER support the UltraSatan?
Yes, but due to incompatibilities with the SCSI standard in old UltraSatan firmwares using firmware version 1.20 or newer is required.
Just like for any device with removable media, for the UltraSatan the settings for removable media drives, which can be configured with HDDRUTIL, are relevant.
Each time when booting HDDRIVER reports a different ID for an IDE/ATAPI/SATA drive.
IDE and ATAPI devices connected to the Atari should not be operated in the Cable Select mode, but should be explicitly jumpered either as master or slave drive.
Are there any limitations when booting from ACSI?
TOS can only boot from the ACSI bus when HDDRIVER is not loaded into TT-RAM.
Are there any limitations when booting from IDE?
TOS can only boot from a drive connected as master drive to the first IDE port if the drive was partitioned while being connected to the Atari's IDE port. This is caused by the wiring of the Atari's IDE port not having the same byte order used by other platforms for IDE.
The Suska board uses the same IDE byte order as other platforms and does not have this limitation.
Is HDDRIVER prepared for new hardware interfaces?
Yes, it is. Even though HDDRIVER itself will most likely not directly support interfaces not fully compatible with the interfaces of the ST, TT or Falcon030, provisions have been made: HDDRIVER and HDDRUTIL support any hardware interface for which a SCSI Driver is available. Developers of new interfaces just need to provide a SCSI Driver for their hardware. See the downloads page for a list of available SCSI Drivers.
HDDRIVER itself includes SCSI drivers for Atari ACSI, Atari SCSI, Atari/Milan IDE, Atari/Milan ATAPI and Atari/Milan SATA.
Data Exchange
Does HDDRIVER support exchanging data with PCs and Macs?
Yes, with the help of the TOS/Windows-compatible partitioning data can easily be exchanged without any additional software with Windows (Windows XP and newer), Linux and macOS. Both FAT16 and FAT32 partitions (the latter only with MagiC or MiNT) can be used for the data exchange.
TOS/Windows compatible media do not work with Windows or macOS.
The media may have been created with the wrong physical drive parameters or with the wrong byte order. Manually adjusting these parameters when partitioning may help.
Why does Windows only find one partition on a removable medium even though there are several?
This is a limitation of Windows versions older than Windows 10: On drives Windows considers removable (this also applies to memory cards) only a single partition is supported.
Why can big TOS partitions not be mounted under Linux?
The maximum logical sector size supported by Linux is 4096 bytes. TOS partitions compatible with TOS 1.00/1.02 and bigger than 128 MiB, and TOS partitions compatible with TOS 1.04 or newer and bigger than 256 MiB have logical sectors bigger than 4096 bytes. Under Linux these partitions can only be used with mtools. TOS/Windows compatible partitions of the same size have smaller logical sectors and can be mounted as Windows partitions.
Can TOS boot HDDRIVER from a TOS/Windows compatible medium?
Yes, provided that the medium is not byte-swapped. TOS/Windows compatible media used with the IDE bus of an Atari have to be byte-swapped, i. e. TOS cannot boot from them. One can boot, though, from TOS/Windows compatible media used with the ACSI or SCSI bus, because no byte-swapping is required for these buses.
Therefore in particular with UltraSatan or GigaFile HDDRIVER can be booted from TOS/Windows compatible memory cards.
Is the IDE transfer rate with HDDRIVER 10 higher for any Atari or just for some models?
The IDE transfer rate with HDDRIVER 10 (compared with previous versions) is up to 15% higher with any Atari (and also with the Milan or with software emulators).
Are the transfer rates of memory cards always higher than those of IDE hard disk drives?
No, because memory cards usually do not support the IDE transfer mode READ/WRITE MULTIPLE. Only some Industrial Grade cards offer this mode. Thus IDE hard disk drives often offer higher transfer rates than memory cards, even though they have longer access times. These differences are clearly measurable with Atari computers.
What is wrong if the same SCSI device is reported for all SCSI IDs?
This happens when the computer's SCSI ID is identical with the SCSI ID of one of the connected devices. Ensure that the SCSI ID of your TT or Falcon, which is stored in the NVRAM, is unique. The computer's SCSI ID should be the highest SCSI ID on the bus, i.e. 7 if only one computer is connected to the bus.
Is there anything to consider when using Cubase Audio?
Cubase Audio does not handle the Falcon's SCSI bus compliant to the standard, which can lead to problems with HDDRIVER 8 and newer. If the CAFFIX software, which is included in the HDDRIVER distribution, cannot put things right and because there are no versions of Cubase where this problem has been fixed, the only work-around is using the last version 7.93 of the HDDRIVER 7 series. This version does not support as many peripherals as current versions of HDDRIVER but is known to work with Cubase. Most functions of the current HDDRUTIL can also be used with HDDRIVER 7.93, by the way.
Users of newer versions of HDDRIVER can request HDDRIVER 7.93 for free by e-mail.
Can I use HDDRUTIL with a different driver than HDDRIVER?
Yes, the maintainance functions of HDDRUTIL only require SCSI Driver and XHDI support. Any driver that provides a correct implementation of these open software interfaces is fine for running HDDRUTIL. This is the case for any type of hardware interface.