The Final Frontier?
@DDFF.ADF - IBM ESDI Fixed Disk Controller
Latest Firmware and ESDI BIOS all
were intel D27128A
(ADP CDDFF.ADF not required / rename to @DDFF.ADF)
@DDFF.ADF - IBM ESDI Fixed Disk Controller
CDDFF.ADF - Init file for _DDFF.ADF
- IBM PS/2 SCSI Adapter w/Cache
(modified, needs no ADP, ROM selectable / German comments) Use this for IBM
ESDI and SCSI Controllers in the same system.
@DFFD.ADF - IBM ST506 Fixed Disk Adapter
90X8969 Marked 90X8971 internally
90X8970 Marked 90X8972 internally
04G3759 Update ESDI firmware
Early MFM Adapter 72X8540
Later MFM Adapter 90X8643
ESDI Hard Disk Attatchment
Install Second ESDI Drive
Using Non-IBM ESDI Drives
8560/8580 HD Cabling Schematic
(Signal and Data)
MFM/RLL Cable Source
Is the IBM Integrated HD Adapter ESDI?
|U3 Intel P8051AH
U5 1700874 (TI CF60025FN)
Y1 20AKSS6M Xtal
U30 is covered with a grey-black resiliant compound that has a heatsink?
pushed into it?? The edgecards at the top are not labelled. U4 and U7 have
the metal can/ceramic construction you love so much.
This "Mystery Card" is also a MFM controller, IBM P/N 72X8540.
It is a early downlevel card, which has been withdrawn with ECA 002, service
code 33 available from 87-06-17 / IBM Boca Raton. This adapter has been used
in early PS/2 Mod. 8560-041 with serial No. range from 8001342 - 8009651
(US production only).
The ceramic shield has been obsolete on the new redesigned MFM
adapter for Mod. 60 & 80. These adapters were already a "factory reworked"
card - first series cards 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 (untypically) unchanged.
[Source: IBM Engineering Changes Group 819 - PC-Family / PS2
Family Service Information Manual, IBM Doc.No. SR28-0280-2 / 3rd Edition
Charles Lasitter impudently asks
U3 Motorola MC3486P
U4 AMD AM26LS3IPC
U5 SSM 8736 24D resistor-
U15 Hitatchi? HM6116LFP-3
U18 Intel P8051AH
Y2 12.0MC TDK
I've had an inquiry about how the 72X8540 ST-506 / MFM adapter
works in Model 8560 computers, and specifically I'm wondering about the usual
stuff: Is this some Unique IBM flavor of ST-506, such that "Don't Bother!"
is the word of the day when it comes to considering non-IBM MFM drives?
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?
From Anarcho-Hacker Peter
From the principle the stuff IBM used there is the usual Western
Digital stuff ... with the major difference of a "BIOS type look-ahead" table
with fixed values and no "User Type". Back in the glorious old days we used
to solve this problem with a software called "SpeedStore". You enter the
BIOS type of a drive which comes closest to the one you want to install and
then override the CMOS settings with the software and a boot-sector resident
Another significant difference: IBM has castrated the 4-device
ST-506 interface down to 2 devices with altering the device adressing 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 adressed with the motor-on and drive
select lines - and a twisted cable for the first drive, which "corrects"
the false adressing logic. The IBM PS/2 BIOS also and consequently supports
only two MFM drives (and two ESDI as well ... they repeated the mistake there
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
ESDI Hard Disk Attatchment
U6 Adaptec AIC-010FL
|U16 See EPROM below
U18 Adaptec AIC-300FL
U33 Intel N8031AH
Y1 10.00MHz Xtal 68X6852
U25 appears to be the Even BIOS, U13 the Odd
Y1 is a unique flat, square clear plastic cased crystal.
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.
EPROM for ESDI Adapter/A
If U16 is 04G3759, then this ECA has already been applied.
Modules with any other P/N should be replaced by using this ECA.
DOWN - level U16
P/N 90X7399, P/N 90X8635, P/N 15F6587, P/N 15F6807 and P/N 91F7430.
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.
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
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
Installing a Second ESDI Drive
From Joe Kovacs
You will need anither data-cable for the new drive. The wide control
cable has a second plug already. To make it a D: drive, you take out
the resistor (Or some models use a DIP switch).
Run automatic configuration, low level format it (CTRL-A on
the main menu), fdisk it, DOS high level format it, and you're away.
PS/2 ESDI Drives
>- Will the HD run in my 8580 even if it is nothe 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 recipie, look HERE
8560/8580 Harddisk Wiring Schematic
to Power Supply
|H-+ | H|
|H | | |
| HD #1
|H-------------\H| HD #2
|H | | /H|
| +------/ H|
|H | | | |
|H---+ | | +---H|
| | | +----------------+
| | |
| | |
| | +---------+
| | |
| | |
J2 J3 |
| IBM HD-Adapter (MFM or ESDI) |
Cable from J1 to HDs #2 and #1 is twisted
for 5 lines 6 to 10 between HD#2 and #1
The segment between J1 and HD#2 is wired 1:1
Cables from J2 to HD#1 and J3 to HD#2 are
both wired 1:1 with no twists
"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
Pin 1 is the common contact
All resistors are 150 Ohms / 0.25 Watts
(C) 1999 by Peter H. Wendt
MCA Mafia of Germany
Dual MFM/RLL Drive Kit 950-0325
28" dual data cable and a 28" dual control cable
MFM/RLL Replacement Cable 950-0326
18" 20-pin IDC to edgecard socket
MFM/RLL Replacement Cable 950-0327
28" 34-pin IDC to edgecard socket
Maxtor 8760E ESDI drive problems on IBM ESDI
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?)
The IBM ESDI controller is a 10MHz controller that has a limit
on the speed (10Mb/s disk-to-interface) and the sectors (36). So most likely
the XT-8760E will not work with that controller. It is a 52-sectors drive
and seems to be an ESDI 15Mhz device as well.
ESDI in a 9577 Bermuda?
From Werner Förtsch
I have a 9577 with an onboard SCSI with one hd drive which was
up to now my boot disk. I found from an old PS/2-80 an ESDI controller and
two ESDI drives which I istalled in the 9577. After long I got the system
up running. My problem now is that my 9577 now boots from the first ESDI
drive. Is there any possibility to boot from the SCSI harddrive in
changing something in the firmware?
1. The ESDI controller has *not* been announced for use in the
later models after Mod. 80 - so it is no good idea to use it in a 77
of any flavour.
2. If any ESDI drive is recognized during setup the machine BIOS
handles it directly on the BIOS-Int Level as system hardware extension (INT
80h device) just like an MFM-drive. The SCSI-Bios is in this case "one step
behind" and the MFM (if any), IDE (on "Lacunas") and ESDI-drives like in
your case will called first and attached to the Int80h device-call.
3. It *might* be possible to use the "Selectable Startup Sequence"
in the machine setup ("Features" in the main menu) - but I truely doubt that
the startup will "know" the ESDI-drive *because* the adapter is notsupported
in that machine. However worth trying and looking atanyway.
4. The 16-bit MCA Stage 1 ESDI-Adapter will most likely have
some influence on the systems performance. I would recommend to remove it
- in case you really plan to do something with the machine and not only do
that for curiosity only. The investment in a new faster and larger SCSI hardisk
(like the IBM DCAS-32160, 2.16GB Ultra-SCSI) is not wasted money. The system
acts a lot more lifely with that.
>Thank you anyway for your helpful information.
Nothing to thank for. I even forgot to mention another nasty
effect of this combination: you cannot run Win95 or WinNT with it. Both adapters,
the IBM SCSI and the IBM ESDI are hardwired to use IRQ 0Eh (14) and are tied
up at the same time. This interrupt-sharing is a technical feature of the
MCA - and causes no problem under DOS / Win 3.x or OS/2 ... but Win95 / 98
or NT cannot handle that, because it runs against their "one device / one
ressource" strategy. So much for the "guys in Redmont" and their understanding
of modern technologies.
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 compatability 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 drive.
Please keep in mind that the 9577 with the onboard-SCSI
is limited to a drive size of 3.94 GB (corresponding to IBM) for the "first
drive to boot from and which holds the system partition". This point was topic
on an older (or: several older) threads in this group. Therefore I recommended
the 2.16GB IBM and not the 4.2GB ... ! But any modern 2GB - 3.5GB drive will
do fine. Quantum makes (made ?) a Fireball with 3.5GB capacity. This would
mark the maximum installable in the Mod. 77. The "over 4GB" appear to be
installable, are even recognized with the exact capacity - but the IML-partition
will not be installable. Now: will install - but will not work. And then
you ran in a nasty IML-error of the I999 00nn category. That
Is the IBM
Integrated HD Adapter an ESDI Controller?
First off: The "IBM integrated harddisk adapter" (Card-ID DF9F)
as it can be found in 50Z, 55SX, 70 and P70 is not a real ESDI drive. It
is more or less technically an MFM RLL 2.7 drive - but combined with a MCA
harddisk adapter in one physical unit. The "ESDI or not misunderstandment"
is caused by the PS/2 BIOS.
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 destops using the integrated harddisk
thingy is only imaginary. The towers (60 and 80) used "Real" ESDI controllers
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.
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