![\"\"](\"https:\/\/i0.wp.com\/avitech.com.au\/wp-content\/uploads\/2017\/01\/drive-and-controller-cropped.jpg?ssl=1\")
<\/a><\/p>\nShown to the right here is an ST-225 (re-badged by DEC as an RD31) and its Western Digital MFM controller model WD1003-WAH, as removed from a DEC Vaxmate in January 2017.<\/p>\n
I will say at the outset that if you have an earlier PC (such as a 386 system) that does NOT have an onboard IDE controller, I suspect that you will have far less difficulty in getting your MFM drive and controller up and running. So please consider that path, if it is available to you.<\/p>\n
The hardware I am using for the purpose of this article is as follows:<\/p>\n
- \n
- A Pentium II motherboard with one ISA slot running “Award Software” BIOS showing “(C) 1994 – 1998”<\/li>\n
- 1 x Seagate ST-225 MFM hard drive<\/li>\n
- 1 x Western Digital WD1003-WAH ISA MFM controller board<\/li>\n
- “Straight-through” 20-way and 34-way cables between the controller board and the MFM hard drive<\/li>\n<\/ul>\n
Configuring the MFM stuff<\/h4>\n
Here are the basic steps that you need to take, to hook up an ST-225 to a Pentium 2 motherboard:<\/p>\n
![\"\"](\"https:\/\/i0.wp.com\/avitech.com.au\/wp-content\/uploads\/2017\/01\/bios-screen-shot.jpg?resize=300%2C169&ssl=1\")
<\/a><\/p>\nFirstly, go into the PC’s BIOS settings (usually accessed by pressing F2 when the PC is booting up) and do the following:<\/p>\n
- \n
- Disable the onboard IDE controller<\/li>\n
- Disable the onboard floppy controller, if the MFM controller board that you will be using (for the MFM hard drive) has its own onboard floppy controller<\/li>\n
- Change the drive settings for the “IDE Primary Master” drive. You will typically have to specify “Manual” (rather than “Auto”) here. Then enter the Cylinder, Head and Sector details for the drive you will be using. For the ST-225, these figures are: 615, 4, 17. Importantly, make sure you change “Access Mode” from “LBA” to “Normal”. If you fail to do this step, the BIOS will pass incorrect drive geometry details to programs attempting to access the MFM drive. For example, for the ST-225, it tells SpeedStor that the drive has 20 Cylinders, 32 tracks and 63 sectors.<\/li>\n<\/ul>\n
Now plug your MFM controller board into the PC’s motherboard. The controller board probably has an ISA edge connector. So you’re going to need a motherboard that is old enough to have at least one ISA slot available.<\/p>\n
Now plug the MFM drive into the controller. There will be a 20-way and 34-way cable. The 20-way cable will be a “straight through” cable. The 34-way cable will either be “straight through” or will have pins 25-29 “flipped” at the drive end. Note that if your cable has pins 10-16 “flipped” it is NOT the right cable and must NOT be used with an MFM hard drive (it is a floppy drive cable). For simplicity, I won’t comment on the “flipped” cable here other than to say that it affects the “Drive Select” jumper that you need to have in place on the MFM drive itself. Check your controller board carefully. It will likely have 2 x 20-way connectors on it (for the first and second MFM hard drive respectively), and it may have 2 x 34-way connectors on it (one for a daisy-chain cable to the two MFM hard drives, and the other for your floppy drives). If the board is not clearly marked, you will need to consult the documentation for the board to make sure you are using the correct connectors.<\/p>\n
On the back of the ST-225 (between the 20-way and 34-way edge connectors) you’ll find an 8×2 array of jumper pins. Assuming you are using an MFM drive attached to “straight through” cables, make sure you have the “DS1″ jumper installed and the other 7 jumpers removed. The DS1 jumper is in the position closest to the 20-way edge connector.<\/p>\n
Make sure the drive has a terminating resistor pack fitted. If you later expand your system to include 2 x MFM hard drives, make sure there is only one resistor pack fitted, and that it is in the drive located the furthest from the controller on the 34-way cable.<\/p>\n
Now connect the power connector. This will be a standard 4-pin connector as used universally on 5.25” floppy drives.<\/p>\n
Booting it up<\/h4>\n
If your drive has a working installation of MSDOS on it and you are exceedingly lucky, your drive may now be capable of booting your Pentium 2 system. This has only worked for me once. I suspect part of the problem is that an MFM drive that was formatted and written on one controller board will often not be readable at all with a different controller board. A second major reason for problems these days is that MFM drives are getting to be very unreliable.<\/p>\n
Running diagnostics on the drive<\/h4>\n
It seems there are a few MSDOS utilities that were useful “back in the day” to perform non-destructive seek and read tests on an MFM hard drive.<\/p>\n
The two that I have played with are: SpinRite II and SpeedStor.<\/p>\n
I’ve not had any luck getting SpinRite II to run on my Pentium II machine. All looks fine until you select an option from the main menu, such as “Quick Surface Scan”. Then it reports an error saying “SpinRite has not found a compatible hard disk sub-system in this computer system, the chosen device’s sector zero is unreadable, or the device is unreadable to SpinRite”<\/em>. I get this error message from SpinRite even when SpeedStor works perfectly well on the same system.<\/p>\n
![\"\"](\"https:\/\/i0.wp.com\/avitech.com.au\/wp-content\/uploads\/2017\/01\/speedstor-manual-setup-menu.jpg?resize=300%2C169&ssl=1\")
<\/a><\/p>\nI have had good results using SpeedStor on my Pentium II machine. Provided you have put the CHS values in the BIOS settings page, and disabled LBA mode (as described above), SpeedStor works well. You can use it to test the controller, and perform non-destructive seek and read tests. More information about SpeedStor (and download links) are available at www.minuszerodegrees.net<\/a>.<\/p>\n
It appears that SpinRite may still be available for purchase from Gibson Research Corporation<\/a>. You may want to check with them, before purchasing, that the current version still supports MFM hard drives on ISA controller boards.<\/p>\n
Formatting an MFM hard drive<\/h4>\n
An MFM drive must be low-level formatted before the MSDOS routines are used to partition and high-level format the drive.<\/p>\n
Some MFM controller boards have on-board BIOS routines that perform this function. If your controller has built-in low-level formatting routines, that is what you should use. Typically these routines are accessed by using the DOS DEBUG command to start the formatting routine in the controller’s BIOS. You will need to consult the documentation for the controller board for further information about this.<\/p>\n
But many controllers do not have an on-board low-level formatting routing. The WD1003-WAH is an example of a controller board that does NOT have an on-board low-level formatting routine.<\/p>\n
Your options then are to use one of the following:<\/p>\n
- \n
- IBM’s Advanced Diagnostics Disk<\/a> (this is referenced in the WD1002\/WD1003 User’s Guide)<\/li>\n
- SpeedStor<\/li>\n
- SpinRite<\/li>\n<\/ul>\n
Some useful links on low-level formatting:<\/p>\n
\nftp:\/\/ftp.seagate.com\/techsuppt\/misc\/format.txt<\/a><\/p>\n
http:\/\/nerdlypleasures.blogspot.com.au\/2016\/05\/working-with-st-506-interface-mfm-hard.html<\/a><\/p>\n
- IBM’s Advanced Diagnostics Disk<\/a> (this is referenced in the WD1002\/WD1003 User’s Guide)<\/li>\n