@DDFF.ADF IBM ESDI Fixed Disk Controller
Early MFM Adapter 72X8540
Early MFM Controller 72X8540
U30 is covered with a grey-black resilient compound that has a heatsink? pushed into it??
The card-edge connectors at the top are not labeled.
The ceramic shield has been obsolete on the new redesigned MFM adapter for Models 60 & 80. These adapters were already "factory reworked" cards - the very first series had the U30 module without the shield and experienced "sudden death" due to some sensibility against electrostatic discharge. Therefore the shield. The P/N for the various cards stayed unchanged.
Source: IBM Engineering Changes Group 819 - PC-Family / PS2 Family Service Information Manual, IBM Doc.No. SR28-0280-2 / 3rd Edition Nov. 1987
MFM Controller 90X8643
Charles Lasitter asks:
Any hope of substituting larger drives for this machine, and if so, what's the point at which it will freak out over translation issues and require exquisitely unique device drivers to step in front of the operating system and hide the messiness?
Another significant difference: IBM has castrated the 4-device ST-506 interface down to 2 devices with altering the device addressing a bit. All drives have to be set to "second drive" (DS1 when counting "0"-based from DS0 to DS3). The two possible drives are addressed with the motor-on and drive select lines - and a twisted cable for the first drive, which "corrects" the false addressing logic. The IBM PS/2 BIOS also and consequently supports only two MFM drives (and two ESDI as well... they repeated the mistake there again).
This part is still missing in the PS/2 Reference PDF section. I *think* I have the MFM controller HITRM or TRM anywhere... but I might be wrong. I PDFed the ESDI and SCSI controllers - which seemed the more important to me.
Single-side load (components on one side only). All major parts are the same as on the later version (including the IDs).
Y1 is a unique flat, square clear plastic cased crystal.
The later version has a double-side load PCB with a slightly modified layout. All resistors and bypass caps were moved to the solder side of the PCB.
ESDI BIOS and Microcode
BIOS Extensions ROMs (ROM images from David Beem)
U14,25 2x 27128 EPROM (128KB, 16x8)
Microcode ROM (ROM images from David Beem)
U16 1x 27128 EPROM (128KB, 16x8)
15F6587 caused a diagnostic formatting problem and an intermittent hardfile delay during system operation (the hardfile light would remains "on" for approx. 13 seconds). also, in rare instances, a write fault could result in a data shift problem during error recovery, which would be detected during read operations and during diagnostics as a "10473" error (ECC error; read error).
15F6807 caused a highly intermittent problem of undetected write faults on the last 1/3 of the last sector written (detected during system read operations and by diagnostics as error code 10473, ECC read errors).
91F7430 experienced a highly intermittent system "HANG" only on 115MB ESDI fixed disks.
David Beem says:
Updating ESDI Microcode
If U16 is 04G3759, then this ECA has already been applied. Modules with any other P/N should be replaced by using this ECA.
Downlevel ROMs: P/N 90X7399, 90X8635, 15F6587, 15F6807, and 91F7430.
Note: Some older versions of direct driver software, which bypass BIOS (basic input/output system) may experience failures accessing the Fixed Disk after the installation of this ECA. This may occur because changing this module may alter how the Fixed Disk subsystem "appears" to the software. Software which uses BIOS is not affected and will function normally. DOS and OS/2 use BIOS.
If the user software fails after this module is changed, the original module should be re - installed, and the appropriate software support function should be contacted for any possible software patches or updates.
After replacement of the module, FRU P/N 92F0062 (P/N 04G3759) advanced diagnostics ESDI fixed disk(s) routine should be run to insure proper hardfile operation.
How Many Drives are Supported?
Two are supported. ESDI natively supported 7 to 8 drives - but IBM (and others) cut that down to 2 or 4... the original IBM / WD controller has two ports for drives.
Installing a Second ESDI Drive
From Joe Kovacs
Run automatic configuration, low level format it (CTRL-A on the main menu), fdisk it, DOS high level format it, and you're away.
Using Non-IBM PS/2 ESDI Drives
>Will the HD run in my 8580 even if it is not the original IBM-HD?
As I understand it, the ESDI drives for the 80-class machines had identity data stored on the drive itself. If it's not an original equipment ESDI drive, or if it *IS* an IBM drive but has since been low-levelled in another (non-IBM) machine, it can't be put back in an 80 unless the Reference Diskette is "cooked". For Peter Wendt's recipe, look HERE.
8560/8580 Harddisk Wiring Schematic (from Peter)
to Power Supply | | +----------------+ | | +----------------+ | |H-+ | H| | | | +------H| | | |H | | | | | HD #1 |H-------------\H| HD #2 | | (Rear) |H | | /H| (Front) | | | +------/ H| | | |H | | | | | | |H---+ | | +---H| | +----------------+ | | | +----------------+ | | | | | | | | +---------+ +-|------+ | | | | Rear | | | Front L_U-----------HHHHHHH--HHH--HHH-------+---+ | J1 J2 J3 | | | | | | | | | IBM HD-Adapter (MFM or ESDI) | | | | | +-+HHHHHHHHHHHHHHH+------------------+---+ +HHHHHHHHHHHHHHH+
Cable from J1 to HDs #2 and #1 is twisted for 5 lines 6 to 10 between HD#2 and #1
ESDI Terminator (from Peter)
How to build your own ESDI terminator:
+----o----o-- ... --o----o----+ | | | | | | | | | | | | +++ +++ +++ +++ +++ | | | | | | | | | | | | |R| |R| |R| |R| |R| | |0| |0| |0| |1| |1| | |1| |2| |3| |0| |1| | | | | | | | | | | | | +++ +++ +++ +++ +++ | | | | | | | | | | | | | 12 11 10 ... 3 2 1 = Pin No.
Pins 12 - 2 are 150 Ohms against Pin 1
MFM/RLL Cables from RadioShack (Dated, for reference only)
Dual MFM/RLL Drive Kit 950-0325
Maxtor 8760E ESDI drive problems on IBM ESDI controller
What could be causing so many 10480s (seek errors)- The drive light flickers on the disk, but is constant on the top HD light, and only gives 10480, even though it looks like it works. The drive was pulled from a 486, what could be wrong with the drive/controller in the model 80? I've read a post about setting a 380MB and other nearly alike ESDI drives similar to mine, but none of the tips work/apply so far. I've even tried custom cables, and different types of 34pin cables. What do I need to do to either get IBM's cable for this card (number please?).
ESDI in a 9577 Bermuda?
From Werner Förtsch:
>Thank you anyway for your helpful information.
So if you just tried it for curiosity - you better leave it. I tried something similar back in 1989 with the Mod. 80-311 to add an SCSI adapter for larger drives and wanted to boot from the SCSI ... did not work. The ESDI always started first. This misbehaviour is (as far as I know) buried in the different handling of ESDI and SCSI from the BIOS.
If anyone else finds a way - okay - I am interested. But as far as I know - and from my own experimenting - it does not work. (Also: Mod. 70 with IBM SCSI and SCSI-HD: also starts from the DBA-2 ESDI drive first)
(Ed. Peter points out the 16 bit compatibility mode the SCSI and ESDI controllers create. So you can run W95 with this setup, but...)
>You are right it will be much better to invest some money for a new SCSI
Is the IBM Integrated HD Adapter an ESDI Controller?
They (IBM) treated the drive as ESDI, because back in those days the MFM harddisk standard was limited to 17 sectors per track (and still is for pure Non-RLL MFM drives) and while the "modern drives" used to be smaller and use lesser platters and -therefore- lesser heads it was easier to translate the physical geometry with e.g. 929 cylinders, 56 sectors and 4 heads into a scheme with 64 heads, 32 sectors and "downscale" the number of cylinders accordingly.
The above example (929 x 56 x 4) would result in 208.096 data blocks á 512 bytes = 106.545.152 bytes. The translation into the 64/32 ESDI scheme would result in the more handy 101 cylinders ... by cutting down the total capacity to 105.906.176 bytes total. However the values 101 cylinders, 64 heads and 32 sectors give a better match into the old XT/AT controller scheme - particularly the cylinder register was -according to the basic WD1007 controller- the problem. It could not hold values over 1.024 ... the ESDI translation in the BIOS opened a more handy way to handle bigger drives up to 1GB IIRC.So after all the "ESDI" in the desktops using the integrated harddisk thingy is only imaginary. The towers (60 and 80) used "Real" ESDI controllers and harddisks.
Secondly the DF9F HD / controller combo was primarily designed as "single device". The later @DF9F.ADF allowed to set one as "primary" and one as "secondary". But as far as I know this has been included to match an early draft of the PS/2 Mod. 90 hardware .... which *had* two integrated harddisk controller ports at the front end of the sysboard. These however had been made non-functional in the later platform BIOSes and don't work. I have played around with them in the early 90s but found no clue to get them working with any Type 1 - 3 platform. As well as Alfred Arnold tried recently - don't know if he gave up yet.
I hadn't been that desperate to try installing the 386DX-20 (Type-0) platform in my 8590 and see if I get the front drivebays going with that.
Due to the lack of appropriate connectors none of the PS/2 machines support two integrated harddisk adapters. These *are* MCA connectors. The 72-pin layout of these drives is basically a slightly stripped-down 16-bit MCA connector. And the planar ADF for e.g. a Mod. 55SX says "4 slots" where the Slots 1 - 3 are for expansion cards and Slot 4 is at the end of the riser card - extended with a flat-ribbon cable over and down to the harddisk.
And - No - you cannot just crimp another 72-pin connector in that cable. There are signals that select the slot number - and that for this "cable port" is fixed set to Slot 4... so any other connector on that cable would signal "Slot 4" to the sysboard. It is -as said- "stripped down"... means: apart from some DC- and GND-wires also "other unimportant signals" are not passed over to the HD-connector.