5.25" External, Internal Diskette Drive, and Diskette
Assembly (Plastic "B" Box)
System/2 External Storage Device Cable (HDI-30 /
DB37 used with P70/P75)
1 - > 72X6759 (360KB DRIVE)
4-> 15F7996 (ADAPTER/A CARD)
* The 8573 requires an External
Storage Device Cable P/N 23F3230, not a 5.25” Diskette
Adapter P/N 72X6757 (attachment
group) (Pass-through only, it uses the planar FDC).
5.25 INCH ADAPTER/A P/N15F7996 (adds
another FDC, needs ADF and device drivers)
- Any external or internal drives attached to it will be seen by the system as logically external. The O/S will assign this drive the next available drive designation. For example: if a 115mb hardfile is installed on a model 8580-111 and it is partitioned as C, D, E, F, the next available drive designation is "G. Your external drive will be booted as "G" during post when the device driver is being loaded.
Early 5.25" 1.2MB / 360KB External Diskette Adapter FRU 15F7996
David Beem says
The switches were used during the development of the adapter. A newer release of the card will not have any switches. The card functions exactly the same regardless of the switch settings.
5.25" 1.2MB / 360KB External Diskette Adapter FRU 15F7996
Allows the 4869-001 or 002 to be attached to the 8550, 8560, 8570, or 8580 system unit or the diskette drive (6451006) to be attached to the Personal System/2 8560 or 8580 system unit. A device driver is used with the 4869 or PS/2 Internal Diskette Drive (6451006). This adapter can accommodate up to two 5.25-inch diskette drives, one external and/or one internal drive in the following system configurations:
TWO DISKETTE DRIVES ONE DISKETTE DRIVE
MODELS 60, 80 MODELS 50, MODELS
ONLY 60, 70, 80 60, 80
EXTERNAL INTERNAL EXTERNAL INTERNAL
4869-001 and 6451006 4869-001 or 6451006
4869-002 and 6451006 4869-002
David Beem weighs in with:
The driver only recognizes the 5-1/4" drive types (360Kb or 1.2Mb), but will read a conventional 1.44Mb drive fine (Identified as 1.2Mb. You can also DRIVPARM it to make it appear like it should.). Can't supplant the regular floppy drives this way though: The attached drive is set up as the next available drive letter. If you have a compressed drive that the host partition is "H:" the attached floppy will be "I:". With both an internal & external drive attached to this board the internal drive is configured first. Only one drive can be on each of the connections. The internal ribbon cable should have no twists.
Tim Clark boasts:
Systems with a 486SX/25MHz [“H”] complex that use the VERIFY function during "Diskette-Like Operations" may fail, allowing bad data to be read from or written to a device without any error indication or other evidence of system failure.
"Diskette-Like Operations" are defined as operations on
any device attached to the diskette drive controller and
are "seen" by the system as a diskette drive, such as
some tape backup devices.
NOTE: Most "H"
complexes have a bad DMA controller [U6 92F1428]. Late
"H" complexes [made early 92 on] can have 10G7808 (known
Good) or 10G4714 (Possibly Good)
H complexes with 48G8042 on sticker below CPU have U23
Systems with the 486SX/25MHz [“H”] processor board and version 1.00 or 1.01 system partition are subject to this problem. Devices that rely on BIOS support are [potentially] supported after an update of the system partition to the latest level.
The 5.25 inch Diskette Adapter/A uses a separate device
driver (not BIOS), and DMA VERIFY. They are exposed to
the problem after updating the system partition.
IBM PS/2 5.25 inch Diskette Adapter/A (#1007) (6451007)
IBM PS/2 4869-001 360KB External Diskette Drive
IBM PS/2 4869-002 1.2MB External
NOTE: H complexi
with the good DMA controller, 10G7808, MIGHT not be
This tip replaces expired ECA100
360KB External Diskette Adapter FRU 72X6758
>[The Drive Connector Assembly] 72X6755 is a card fitted to a plastic bracket making it fit into the second floppy bay of the 8570 (Ed. works with 50/60/70/80 card edge floppy) I got it from. It had a connector on the side (34 pin header), which was connected by ribbon cable to the MCA card using a 34 pin edgecard socket (3M 5934).
David Beem again lays it out by saying:
ADF Sections AdapterID DFFAH AdapterName "5.25-inch Diskette Drive Adapter"
DMA Arbitration Levels
Drive Connector Assembly 72X6755
Used on 8550, 8560, 8570, and 8580 models with card edge floppy sockets. Not for use with 8565 and 8580 A21 / A31.
34 position card edge slips into floppy socket and assembly clicks into place like a normal floppy.
Note the 34 pin header on underside of Assembly. The 34 conductor ribbon cable then goes over to the 5.25" 360KB External Diskette Adapter FRU 72X6758, where the card edge socket connector fits onto P2.