mark@promark.UUCP (Mark J. DeFilippis) (02/19/90)
It has taken over 6 months, but the "SCO - TWO CONTROLLERS" problem has been resolved and I think much of my findings can benefit people, hence this posting. The following has been found to work together: Machines tried: SYSTEM CPU SPEED ALR 386/2 16 mhz ALR Flexcache 386/25 25 mhz Hauppauge 386 16 mhz Hauppauge 386 20 mhz JDR Microdevices 386SX 16 mhz SETUP: Primary Controller Secondary Controller master file 36 37 AT Bus interrupt 14 15 Controller combinations that worked fine: M - Miniscribe m - MFM e - ESDI S - Seagate r - RLL Controller Drive 0 Drive 1 Primary WD-1006V-MM1 Mm-6085 Mm-6085 Secondary WD-1006V-MM1 Mm-6085||Sm-ST251 NONE Primary WD-1006V-MM1 Mm-6085 Mm-6085 Secondary WD-1006-WAH Mm-6085||Sm-ST251 NONE Primary WD-1006V-MM1 Mm-6085 Mm-6085 Secondary ACB-2372-C Sr-ST27R-1 Sr-ST277R-1 Primary WD-1006-WAH Mm-6085 Mm-6085 Secondary ACB-2372-C Sr-ST27R-1 None Primary WD-1007 Me-3180E Secondary ACB-2372-C Sr-ST27R-1 None The original problem of drive Re-Cal was solved purely by trial and error. It seems in ALL of the above machines and combinations if the 34 pin cable on the secondary controller was a STRAIGHT cable with no twist (which in that case drive 0 is DS1, drive 1 is DS2) there was ALWAYS a re-cal problem. You could write to it, read from it, but in the middle of the read the drive would Re-calibrate and seek at 1/2 step rate to cyl 0. This was unacceptable. If a cable with a twist for drive 0 was used and all drives on secondary controller set to DS2, the Re-cal problem went away. I don't have an AT Technical ref. Manual (Someone borrowed it...), so I don't know what pins these are, hence I could not analyze the reason. It seems only a cable with a twist will yield good results. (Those of you out there with a secondary controller, if you are running a cable with no twist I will be very surprised, send me Email please as I am attempting to gather as much data as possible. Many people wrote to me stating that some combinations of controllers seem to work together and some don't. Originally this seemed to be the case, but after noting the "twisted cable" phenomena, I have been able to get the above to work together when I previously could not. Some said they were trying to get two WD controllers to work together for months with no success, One person wrote and said he had two WD-1006's working together. It turned out later on that indeed he had a 34-pin control cable with a twist. Check if your cable has a twist. About the ACB-2372B. It seems that controller is no longer available. The new version ACB-2372C does not have the Interrupt Jumper (J13 on the old 2372B)! (So much for "If it aint broke don't fix it", even if it is slow :-)). However, The Gold fingers for D6 and D7 are still there. This is not the case with the WD-1006 boards. 1006-VMM1 boards are a _REAL_ hassle to modify for interrupt. The ACB-2372C also does not have pin J9 which disables the floppy. When I called Adaptec they told me "There was absolutely no room for the trace to allow the alternate interrupt line". The fact that the pins to disable the floppy were left off was an oversight, but the traces still run to where the jumper pins should be. So, to set up this controller you should low level format the drive. Then change the controller. Solder across pin J9 to disable the floppy if desired. Then solder finger D6 and D7 together. This changes the interrupt from 14 to 15. You do not have to use interrupt 15, but it is the most convenient since the fingers are adjacent. I then used a razor blade to lift the D7 gold finger right off the board once I confirmed it worked. Slap a jumper on J2-1 to configure the secondary controller at the H170 port address. Don't forget to change the NDISK kernel parameter and relink the kernel. NDISK specifies the maximum number of Hard Drives. Then just execute per the release notes: mkdev HD 0 1 Again, thanks to all those who have provided their configuration information and aided in my attempts to get two controllers to work. I hope that this twisted cable phenomena will help others who may be having the same problems. -- Mark J. DeFilippis SA @ Department of Mathematics and Computer Science Adelphi University, Garden City, NY 11530 (516) 663-1170 UUCP: philabs!sbcs!bnlux0!adelphi!markd