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Usage of command line options P0, P1, S0 and S1 in version 4N - (without the PCI bus numbers b:d:f) will disable the use of read/write DMA commands. This was initially entered as a bug in version 4N but it is not a bug. When the PROMPT option was added, the functionality of these options was changed but the User Guide and history files did not indicate this change. When using version 4N (and future versions) use either the b:d:f:x option, or the PROMPT option, then use of the read/write DMA commands will be possible.

BUG in version 4N: CF devices implementing DMA commands - If a CF device implements READ/WRITE DMA commands, ATACT may generate only READ DMA commands. Version 4N doesn't actually support READ/WRITE DMA on CFA devices. Version 4P will correctly support these commands (only in TrueIDE mode).

SEQ=N vs. SEQ=WRN option and data compare errors: Running ATACT with SEQ=N (the program's default) can make locating the source of data compare problems more difficult to find in the drive's hardware and/or firmware. Use SEQ=WRN to see if the problem that can be found using only a write pass followed by a read pass. If there are no data compare errors, then use SEQ=N -- It is possible that more random write/read and other randomly executed commands, such as the power management commands, are required to create the data compare error.

MAXSIZE and MINLBA options: Use these options to test less than the full drive. For example, if you have a drive with 400M sectors (about 200GB) you could use these options to test the first 10GB (about 20M sectors), the middle 10GB or the last 10GB:

• MAXSIZE=20M - test the first 10GB (MINLBA defaults to 0M).
• MINLBA=190M MAXSIZE=20M - test the middle 10GB.
• MINLBA=380M - test the last 10GB (MAXSIZE will default).

The DUMPCHT option - finding data compare errors that happen during the SEQ=R pass: When using SEQ=WRN you are getting a data compare error during the SEQ=R pass that seems to have happened during the SEQ=W pass. Of course the write commands that caused the problem are no longer in the Commmand History Trace (CHT). But every sector that is written contains the command number that wrote the sector. For example, when some sector is read it contains the wrong data (the data for some other LBA) - using the command number in this incorrect sector, rerun the program with the same command line options and add the DUMPCHT=n option, where n is about 30 more than the command number in the sector with the incorrect data. This will cause the Command History Trace (CHT) to be displayed during the SEQ=W pass at the write command about 30 commands following the command that wrote the bad data. Of course DUMPCHT=n can be using at other times, not just to find problems in a SEQ=W pass.

Usage of command line options P0, P1, S0 and S1 in version 11N - (without the PCI bus numbers b:d:f) will disable the use of read/write DMA commands. This was initially entered as a bug in version 11N but it is not a bug. When the PROMPT option was added, the functionality of these options was changed but the User Guide and history files did not indicate this change. When using version 11N (and future versions) use either the b:d:f:x option, or the PROMPT option, then use of the read/write DMA commands will be possible.

Please check again some day soon.

Please check again some day soon.

BUG in version 1N: CF devices implementing DMA commands - If a CF device implements READ/WRITE DMA commands, ATAMDT may generate only READ DMA commands. Version 1N doesn't actually support READ/WRITE DMA on CFA devices. Version 1P will correctly support these commands (only in TrueIDE mode).

SEQ=N vs. SEQ=WRN option and data compare errors: Running ATAMDT with SEQ=N (the program's default) can make locating the source of data compare problems more difficult to find in the drive's hardware and/or firmware. Use SEQ=WRN to see if the problem that can be found using only a write pass followed by a read pass. If there are no data compare errors, then use SEQ=N -- It is possible that more random write/read and other randomly executed commands, such as the power management commands, are required to create the data compare error.

MAXSIZE and MINLBA options: Use these options to test less than the full drive. For example, if you have a drive with 400M sectors (about 200GB) you could use these options to test the first 10GB (about 20M sectors), the middle 10GB or the last 10GB:

• MAXSIZE=20M - test the first 10GB (MINLBA defaults to 0M).
• MINLBA=190M MAXSIZE=20M - test the middle 10GB.
• MINLBA=380M - test the last 10GB (MAXSIZE will default).

Bug in version 1A: Identify data not displayed correctly. The ID data returned by INT 13H AH=25H is not displayed correctly. This bug is fixed in version 1B.

Please check again some day soon.

Technical Support email address: After checking this page if you still have a question or problem send an email to