View Full Version : Ultra DMA modes within HDST 3.1.1

04-03-2001, 04:02 PM
Can anyone tell me what the Ultra DMA (timing) modes (i.e. "Mode 1", "Mode 2" ect.) specifically represent in HDST v3.1.1? The subject is approached on pages 30 and 31 of the HDST user guide. What mode would be best/appropriate for a start-up Seagate Ultra ATA 66 (p/n ST330630A) in a rev1 B& W G3?

04-15-2001, 09:09 PM
They don't represent anything but archane timing parameters defined by the T13 committe of ANSI. Therefore, they specifically represent Ultra DMA Modes 0, Mode 1 and Mode 2, etc. I can tell you that the speeds roughly translate as follows (if my memory serves): Mode 0 -> 15.3 MB/sec; Mode 1 -> 23.6 MB/sec; Mode 2 -> 33 MB/sec. If your really curious about the timing parameters I recommend downloading the final working draft of the ATA/ATAPI 4 spec from <ftp://fission.dt.wdc.com/pub/standards/x3t13/project/d1153r18.pdf>.

As far as the correct setting for your goes, it's impossible to predict due to the flakey ATA chip in the early B&W. Ultra 2 is fastest but make sure you can checksum a large disk image at that speed before you trust your data to it. Read our testing info thoroughly. It was written for exactly your situation.

Chris Karr
Intech Software Corp

04-15-2001, 10:30 PM
To be safe and conservative, set it first to Mode 0. Get a large .smi file such as Apple's OS 8.6 Update. Double click on it to let Disk Copy 6.3.3 expand it. Look for checksum errors. If you get none, you're good.

Move up to Mode 1 and go thru the same process again, etc.........

04-16-2001, 10:00 PM
What is this? No one has questioned my technique in all of 24 hours!

Chris; is that OK for a SCSI guy?

[This message has been edited by Louie (edited 16 April 2001).]

04-17-2001, 12:09 AM

05-04-2001, 03:11 PM

Thank you for the info! I really appreciate it. http://macgurus.com/infopop/emoticons/icon_wink.gif

05-04-2001, 10:54 PM
I just used v 3.2 on a new Maxtor Diamond Plus 60 that I put in the wife's Beige G3. It's much easier than I described below. The Intech software is smart enough to set the proper modes to compensate for the lousy Apple ATA controller. Then you run "Integrity" which is part of the package. If any errors show up, you can slow things down by changing the modes. The proper mode settings for the beige G3 allows about 16 MB/sec sustained transfer rates with the Maxtor. This is a hell of a lot better than the Apple issue 4 GB IBM which reads at 10 and writes at 7.