Differential SCSI-2 Fast/Wide Adapter FRU 11H3599 / 11H7660
  Rework on 11H7660 Front
  Rework on 11H7660 Back
Enhanced Differential SCSI Fast/Wide Adapter FRU 52G3380
Jumpers on the Fast/Wide
68 pin Internal Connector
Drive connector
SCSI device and adapter configuration flexibility 
SCSI Device Order
Maximum SCSI Devices Supported
Fast POST Consequences
ADF Sections
   ESDI Requirements

RN1,2,3 Removed on RS/6000 systems when a high-reliability configuration is used (one of them there "Y" arrangements illegal to normal SCSI users).

  The SCSI-2 Differential Fast/Wide Adapter/A supports an internal single-ended and an external differential SCSI bus. 

FRU 11H3599
To date, all attempts to get this RS/6000 adapter to work in a PS/2 have failed. Although the chipset is the same as on the Fast/Wide, the rev .71 flash update does not recognize a F/W chipset. 

OS Limits
  Not all Micro$haft products support multiple IBM SCSI adapters gracefully. W9x cannot handle shared IRQs and will drop into MS-Doze (In)compatibility mode.  Win NT, OS/2, Linux and other unixes can handle shared interrupts. 

Fast/Wide in 8590/8585
   If you don't have a Type 4 complex on a 95A (dual serial/dual parallel), you may not be able to use some features of the Fast/Wide, most notably Internal/External Bus Mode. You need to run SCSI2FW.EXE to update the system partition. 

FRU 11H7660
   Much to my suprise, the 11H7660 configures fine, flashes to .71, and works like a normal F/W.

Front 11H7660 DFW Rework

Rear 11H7660 DFW Rework

Rework A comes off the fourth MCA contact.
Rework B comes off the solder pad marked with a V.
Rework C comes off the third pin on the upper left of U23.
Rework D comes off the second pin of U23.

Jim Shorney rains on our parade- he warns that foil cuts may have been made in addition to the rework wires. 

       The SCSI-2 Differential Fast/Wide Adapter/A is a dual-ported, fast and wide (two bytes wide) SCSI Micro Channel adapter that provides synchronous SCSI bus data rates of up to 20MBps.  The internal SE port is capable of addressing up to seven SE SCSI devices and the differential external port is capable of addressing up to seven differential SCSI devices, providing a maximum of 14 devices per adapter.  The number of physical devices attached to each port is limited by SCSI bus cabling restrictions.  The external differential port can support a total cable length of 25 meters (82 feet).
       Additional system, subsystem and high-availability connections are also available with the differential system-to-system and Y-cable features.

    The entire datecode is not bad, but because of this, the whole lot is suspect.  If you have any of the symptoms below, keep in mind the SCSI-2 F/W adapter may be the problem.

   There are three types of symptoms you may see....
   1)  Checkstops (SIO BUS 0 or 1  PARITY) 
   2)  System Hang/Unresponsive
   3)  DMA_ERR in the Error Log

Affected Controllers
SCSI-2 F/W Controller Type     FRU p/n       U-location
 * Integrated                  52G4325         U60
 MicroChannel SE               11H3600         U5
 MicroChannel DE               11H7660         U13
 Enhanced Microchannel DE      52G3380         U16

    Note (*):   The Integrated SCSI-2 F/W controller is the one on the I/O planar of the 7012-380/390/39H and 7012-3AT/3BT/3CT systems.

MF-SM Series MF-SM150

Jumpers on Fast/Wide
   The results of shorting the jumpers ranged from no difference, slight performance hit (%10 overhead increase) or a system-halting error. Leave them off. RS6000 documentation says the jumpers are to be left open. 
   J5 grounds out pin 33 on the internal SCSI controller 82G2645. Purpose unknown. 
   J6 grounds out pin 1 of U1 and U2. Marked "Boot Block Enable"

68 pin Internal Connector on D F/W SCSI Adapter
  This is a "mini-Centronics"  or a Vesa Media Channel plug. The ANSI moniker for it is a "P" plug. Also seems to be used for SCA drives... Hmm...

AMP (and Tyco)  # 1-557089-2
Looks like THIS or if you want the page go HERE

Newark Electronics 97F8813
   CHAMP. 0.050 I Series Interface Connectors For VMC Applications: 68-Position 

  Designed for use with 30 AWG solid conductors on .064mm (.025") centers.  look HERE

Molex 71660i  Molex part 15-92-3068 1.27mm (.050") Pitch
  EBBI™ 50D - Receptacle, Vertical, IDT 71660i Looks like THIS
   Terminates to 30 AWG solid or stranded.025" ribbon cable or laminated discrete wire cable 

Drive connector
The 68 pin crimp-on device connector. Dalco 59611  $4.25 

SCSI Device Order
   SCSI device logical ordering and hard drive letter assignment (e.g. C:, D:) sequence is determined by the SCSI adapter slot numbers, internal or external SCSI bus connection, and SCSI ID of the connected devices. 
   Adapters are scanned for SCSI devices beginning with the SCSI adapter in the lowest numbered slot.  Devices connected to the same adapter are logically ordered according to device SCSI IDs in order from 7 to 0 and then from 15 to 8 according to the priority scheme defined by the SCSI standard.  Devices connected to a SCSI-2 Fast/Wide adapter's internal bus connector are ordered logically before devices connected to the external bus of the same adapter. 

Maximum SCSI Devices Supported
   Wide SCSI devices support 16 possible SCSI ID values.  The adapter uses one these values; therefore, the SCSI-2 Fast/Wide adapter can connect up to 15 fast and wide devices internally or externally in any combination using the remaining ID values.  Narrow SCSI devices support 8 possible SCSI ID values; therefore, up to 7 narrow SCSI devices can be connected to the internal or external SCSI busses in any combination using the remaining ID values.  Wide and narrow devices may be mixed on the same internal/external bus by using the proper combinations of SCSI bus cables, terminators, and/or SCSI connector convertor adapters. 
   NOTE: Use of a 8 bit (Narrow) cable forces the controller to default to only 7 devices supported on that port, even if all devices on that cable are Wide. 

Fast POST Consequences
   Some newer systems also provide a FAST POST option which may be selected from the system configuration menu or from the IBM logo screen.  When this option is selected, the system will not check for the presence of newly added SCSI devices unless F1 is also pressed while the IBM logo is displayed.  Newly added SCSI devices will not be configured nor will an error occur if the fast post option is chosen as the default.  To access the system configuration program, press F1 while the IBM logo screen is displayed to configure the new SCSI  device(s) initially. 

I/O Address 
   I/O address for the adapter. Each adapter must have a unique address range.
    <3540-3547>, 3548-354F, 3550-3557, 3558-355F, 3560-3567, 3568-356F, 3570-3577, 3578-357F, 3578-357F 

DMA Arbitration Level
   Arbitration level used by the adapter to transfer data. 
   <C>, D, E, 8, 9, A, B, 1, 3, 5, 6, 7 

SCSI Adapter Address (ID)
   SCSI ID of the adapter. Usually ID7, unless you have specific requirements.
   Adapter IDs available are: <7>, 6, 5, 4, 3, 2, 1, 0

Move Mode Support
   Enable or Disable Micro Channel Subsystem Control Block Move Mode This is the second mode of SCBA (first is locate mode) which permits the system processor to move the subsystem control blocks to the adapters directly. 
   <Enabled> or Disabled 

Wait State Support
   Enable or Disable Bus Master wait states. If the target expansion card is an older card, it may not be able to process commands or data from the busmaster fast enough, and when queried by the busmaster, it replies with "not ready". By inserting a wait state, the slower card has more time to signal "ready". Enabling wait states can slow your busmaster down. 
   <Disabled> or Enabled 

Data Parity Exception Handling
   This Adapter can generate and detect data parity on Micro Channel. Data parity must be supported on both ends of an across-the-bus transmission in order for this error detection process to be effective. A data parity enable (-DAPAREN) bus line to the system and other expansion boards is enabled when data parity is being used. If the System does not support Data Parity Exception Handling, this feature will always be disabled. 
   <Enabled> or Disabled 

Selected Feedback Return Exception
   Whether a busmaster will report errors detected in the select-feedback-return process. 
   When enabled, the busmaster monitors the selected feedback return and card-selected feedback buslines. The return line tells the master that it's target expansion board is responding properly to being addressed for a read or write operation. If the bus master does not recieve this signal (and SFR has been enabled) it may mean that the expansion board is not operating properly or that the signals themselves are not properly traveling across the expansion bus. This error causes the master to immediately halt the transfer in progress and notify the host system of the error using an interrupt. NOTE: The SFR must be ignored for PC compatibility. If the System doesn't support the Selected Feedback Return feature, it will always be ignored. 
   <Enabled> or Ignored 

100ns Streaming Data Transfer Support
   This provides better performance. It will always be disabled if the system doesn't support it.
   <Enabled> or Disabled 

Target Mode
   Target mode should be disabled only if this system is sharing SCSI devices with another system and there are more than 15 devices to be shared.  Only 15 devices can be configured on each adapter. When target mode is enabled, this adapter appears as a processor device on the other system and unless you have specialized software that can communicate between the two systems through these processor devices (peer-to-peer communication), there is no advantage in having
target mode enabled.  When target mode is disabled, this adapter does not appear as a device to the other system, and one more device can be shared by the two systems.  If your system is not sharing any SCSI devices with another system on this adapter, it does not matter whether you enable or disable target mode. 
   <Enabled> or Disabled 

SCSI Disconnect
   Disconnect is a SCSI-bus procedure in which a device logically stops communicating with the adapter during certain operations and then reestablishes communication with the adapter when the operation is complete.  Disconnect should not be confused with the 'Presence Error Reporting' option for a device in 'Set and view SCSI device configuration.'  If you are using an operating system that is single-threaded and issues commands to only one device at a time (such as DOS or Win95), disabling SCSI disconnect might result in a slight performance improvement.  If your operating system is multi-threaded (such as OS/2), disabling SCSI disconnect will degrade the performance of the SCSI subsystem. 
   <Enabled> or Disabled

Fast SCSI - External
  If you have Fast SCSI devices attached externally, enabling Fast SCSI improves performance : 
  - One external SCSI device enclosure model 3511. 
  - Up to three external SCSI device enclosures model 3510. 
  - Any external configuration where SCSI cable length isn't > 3 meters. 
   <Disabled> or Enabled 

Wide SCSI messages - External
   This should be 'Enabled' unless you have a Wide SCSI device attached to the adapter through a narrow (8 bits wide) external interface cable. 
   <Enabled> or Disabled 

Wide SCSI messages - Internal
   The setting for this should be 'Enabled' unless you have a Wide SCSI device attached to the adapter through a narrow (8 bits wide) internal interface cable.
   <Enabled> or Disabled 

Internal/External Bus Mode
   'Separate', SCSI devices on external SCSI bus connector can have the same SCSI ID setting as other SCSI devices connected to  internal SCSI bus connector on the same adapter.
    'Combined', all devices connected to this adapter must have unique SCSI ID settings regardless of which SCSI bus connector is used to attach the devices.  Default is 'Separate' unless you are using an operating system device driver that does not support independent operation of the internal and external SCSI busses on the adapter. 
    <Separate> or Combined 

System Determined
ROM Address Range
   Address of the 32K block of memory assigned to the adapter. Only one SCSI Adapter will have the ROM assigned, and any other SCSI Adapter installed will share that address range. 

ESDI Requirements
   If the ESDI adapter is also installed, then the address of the SCSI adapter must be greater than the ESDI adapter address.

ESDI Requirements
   If the ESDI adapter is also installed, then the address of the SCSI adapter must be greater than the ESDI adapter address.