Reference and Diagnostic Disks
Bermuda Planar (9576/77)
   Bermuda vs. Lacuna Risers
   Built-in SCSI
   Bermuda Overclock
Lacuna vs. Bermuda
   Upgrading Planars
   Devil's in the Details
77 Control Module Header Pinout
76/77 Power Supply
PCMCIA Adapter Mounting
76 Case Stand
   AVE Slot

Refdisk and Diags
7677ref.exe 76/77 Reference Diskette Version 3.10 
7677diag.exe 76/77 Diagnostics Diskette 

Bermuda Planar
J1 Mouse Port 
J2 Keyboard Port 
J3 Parallel Port 
J4 Serial Port 1 
J5 Serial Port 2 
J6 SCSI Port (mini-C60) 
J7 Internal SCSI Port (50 Pin) 
J8 4 Pin Header Solder Pads, unk 
J9-J12 72 Pin SIMM Sockets 
J13 MCA Riser Card Slot 
J14 3 Pin  Solder Pads, Speed 
J15 3 Pin Header Solder Pads, Unk 
J16 44 Pin Floppy Header 
J17 Power Connector 
J20 8 Pin Header  LogicLock? 
J21 3 Pin Header outline, JMP2 
J22 JMP1 Power On Password 
OS1 25 MHz  Line Interface? 
OS2 32 MHz Drives 80C188 
OS3 22.1184 MHz  Serial Ports 
OS4  Solder Pads for 50 MHz Osc 
OS5 66 MHz  halved for 33MHz 
OS6 24 MHz  Floppy Controller
OS7 40 MHz MCA Bus Clock 
OS8 14.3181 MHz Oscillator 
R14, R31 PTC Resistors Transorbs 
ST1, ST2 Resistor Networks
U12 N80C188-16 SCSI Controller 
U14 Sony CXK5864BM-10LL 
U15 Dallas DS1285Q 
U19 SRM20256LM-12 
U20 39G2066 
U23 Hitatchi HM514280ALJ8 
U24 TI 84F8324 SCSI Line Interface 
U28 Dallas DS1210S 
U31 33F6715 
U32 15F6903 
U42 10G4672 DMA Controller??? 
U48 Solder Pads for SMD 486SX? 
U49 Socket 1 for 486DX CPUs 
U60 64F8781 Memory Data Buffer 
U65 System EPROM 39G3299 
U76 Floppy Controller 
U78 89F5724 Memory Controller 
U79 89F5415 MCA Bus Controller 
U84 63F7520ESD 
Y1 32.768 KHz Xtal

U76 This can be either the N82077AA (used on the 90 and 95) or it can be the National Semiconductor PC8477AV-2 floppy controller. A few systems have the 82077SL controller, PLUS U65 System EPROM 39G3299 is soldered directly to the planar (no PLCC socket needed) 

From Peter 
   Hmmm. Looks as if the U19 SRAM (32K x 8) belongs to the U12 80C188 and the U23 SRAM (32K x 8) is related to the U32 15F6903 as "sort of" command cache. 
 The 25MHz osc- Clock chip for the two SCSI "companion" chips U31 33F6715,  and U32 15F6903 
    U23 seems to be the RAM for the 80C188 SCSI busmaster controller. (32K x 8 bit - 62256 compatible IIRC) 
   Don't know what U14 (8K x 8bit SRAM) is for. I think it is the "external buffer" for the DS-1285Q, which is assisted by the DS-1210S and the 3V battery. 

Remind that there were several "Bermuda" boards: 
- the 486SX (25/33MHz jumperable) with "Upgrade CPU" socket 39F2668 
- the 486DX (33MHz only) with the CPU in the "Upgrade socket" 39G2669 
plus the 39G5698 (SX-33), 39G6086 (486DX2-33/66 MHz ),  39G6444 (DX2-33/66 special bid for Pinnacle CD-ROM Bootable Systems) 

Bermuda vs. Lacuna Riser Card
   If you think you can just drop a Lacuna into a Bermuda system, you are wrong. The riser cards have physically different edge contacts. Note the edge connectors. The 76i bus adapter support (individual FRU) is 61G2289. This FRU is for the bracket alone. 

Bermuda Riser FRU 87F4833

BT1 CR2032 
J1 Base Video Extension slot (For XGA/XGA-2) 
J2 32 bit slot 
J3 Auxiliary Video Extension slot 

   Note the "BVE" like connector at the left (rear) of the riser. As Bermudas do not have on-board video, the riser needs a BVE slot. This riser has the spring clips just like the Lacuna riser. 

Bermuda 77 Riser FRU 87F4836

J1 is BVE slot, J2 is AVE slot. BT1 is the beloved CR2032.

 The seperate riser card (riveted onto bracket) is FRU 87F4836. My HMM has the bracket/riser as FRU 87F4836. The bracket/riser is marked with a sticker as P/N 39G2063 

Onboard SCSI
From Peter
   The onboard SCSI of the 95xx is often refered as "Spock-Prime" - and is (almost) identical to the later SCSI with cache ... with the exception of the cache, which it hasn't got. From the design it is *very* similar to the short SCSI without cache, which has an 80C188-16 as well. The SCSI microcode however is part of the machine BIOS stored in a single small 16-bit PLCC Eprom if I remember correctly. There is a part of the SCSI code also included in the IML. 
   This adapter can be found on the 9556/9557, the "Bermuda" 9576/9577 - and the "small" 9585-0Xx. The earlier PS/2 85xx use an onboard version of the old, long SCSI adapter without cache - like the 8556/8557 and 8573-161 and -401 (P75). 

    If you look closely at the 9577 planar you will find some SMD transistor "of the bigger kind" and some stuff that looks like "auto-termination". In addition the onboard SCSI adapter of the "Spock-Prime" is described as "SCSI-2 compliant" ... which extends on the command set in the first place, the enhanced SCSI translation and on the electric interface as well I think.  But not on the speed of course, which is 5 MB/s SCSI-1 standard. 

From IBM
The SCSI controller is integrated in the planar so a slot is not required. 

     Supports SCSI Common Command Set Version 4.B (SCSI-2 Compliant) 
     Local Bus increasing data transfer speed 
     Support for mixed SCSI devices and capacities 
     Attachment of up to 7 SCSI physical devices (internal and external) 
     Allows multiple SCSI initiators for device sharing 
     SCSI Data Transfer Rate - up to 5.0 MB/sec 
     Supports Synchronous and Asynchronous SCSI Data Transfers 
     Supports disconnection/reconnection of SCSI targets 
     Automatic external SCSI bus detection (disables internal planar terminator automatically) 
     Slew rate controlled SCSI drivers and filtered SCSI receivers for high data integrity. 

Bermuda Overclock
From Peter Wendt 
   I tried the oscillator swap (Ed. OS5 upped to 80.000 MHz) on a "Bermuda" - with less success so far. The system tries to come up but lands in a number of errors, from which the "trivial ones" (162/163/161) are logically a symptom of the board removal and a total loss of CMOS contents. But the machine comes up with a I9990021 - even with a proper ref-disk in A: ... chokes on reading any other floppy. Guess it is the same problem as with the Mod. 90/95. 
   I tried running the machine with a DX4-33/100 in 2x mode (jumper on interposer), which is known to even work at 50MHz input clock. No go. The cursor in the phase before memory count seems to blink a bit faster ... but then the machine hangs with I999-error after the count.  Configuring it properly and *then* swapping the oscillator (which is a bit tricky) did not work either - ran into a solid I999 0022 (invalid IML). Restoring system partition from diskettes also failed. 
   Conclusion: overclocking isn't a  good idea. At least not with this (too). Any other experiences ? 

Upgrading planars
  You can upgrade any current PS/2 76/77 or PS/2 56/57 with the new PS/2 Planar Upgrade. You'll gain all the advantages of the new 76/77 i and s systems. Current 76/77 systems will perform up to 38% faster while keeping everything else intact. 

Devil's in the Details
From  Carlyle Smith

   There are two broad classes of box designs that led to the 9576 and 9577. 
Narrow box:
8556 --> 9556 --> 9576 --> 9576i (IDE) and 9576s (IDE plus SCSI) 

Taller box:
8557 --> 9557 --> 9577 --> 9577i (IDE) and 9577s (IDE plus SCSI) 

Of course, the 855X were 80386DX or 80386SLC, so they used a completely different system board. The 9576 and 9577 used the same system board (=Bermuda), one with SCSI built into the board (=Bermuda). The 9576i and 9577i (Lacuna system board) were made in  two different clock speeds -- 25MHz and 33MHz.  Their system board FRU part numbers were: 

    25MHz only:  95G9691 (not  streaming transfer capable) 
    25<-->33MHz switchable 96G1305 
    33MHz : 95G9692 

   A 957Xs is only a 957Xi with a modified Future Domain SCSI card added to one of the adapter slots on the bus riser card, to handle internal/external SCSI devices. 
   The models used the following riser cards (non-interchangeable, AFIK)(* means CMOS battery located on riser card): 

Parts Comparison:
    9576i/s  3-slot bus riser assembly    68G2706
             plus card guide              92F0244
             plus card guide ass'y C2     92F0243
             plus bus adapter support     71G5711

    9576     Bus adapter*                 87F4833
             plus bus adapter support     96F7777
             Plus card guide/spkr ass'y   92F0244

    9556     Bus adapter*                 79F7210
             plus bus adapter support     96F7769

    8556     Bus adapter*                 79F7210
             Bus adapter/spkr support     79F7213

    9577i/s  5-slot bus riser assembly    68G2709
             plus card guide              92F0042
             plus card guide ass'y C2     96F7758

    9577     Bus adapter riser card       87F4836
             plus adapter card guide      92F0042

    9557     Bus adapter riser card       41G3877
             plus adapter card guide      96F7758

    8557     Bus adapter riser type 1     85F0056
                            or type 2     41G3877
             plus adapter support guide   92F0042

   So you see, it is important to know both the part number and clock speed limitation of the Lacuna-type board, and to have the correct bus riser card for the particular box/system board. In other words, you cannot really upgrade a 957X to a 957Xi/s without changing the riser card as well as the system board! 

   I do not know how to verify the riser and bracket stuff. If you know what bracket/riser will or won't work with a Lacuna, tell ME!

IBM 76 Security Cable Cover . Hmm, never seen one. 

76 / 77 Control Module Header Pinout
The pinout of the standard 76 / 77 speaker/power switch module is 

PWR Sense +
Audio -
Audio +

Bermuda BVE Slot
   On the 9576, Slot #1 is the BVE Slot, Slot #3 is the AVE slot. 

Parallel Port

ECP Support
Does the 77 even support ECP? My printer/CD/ZIP drive doesn't work... 

From Peter
Do the following: 
- boot into reference (either disk or system partition if one installed) 
- enter "Set configuration" 
- find the "Parallel Port DMA" and set it to "Disable". 
- press [F10] to store the config ... [F3]/[F3] to leave. 

   That should fix the problem. The 9577 -as most PS/2- has a "DMA-arbitrated" LPT-port, which is neither ECP nor EPP, only "sort of". The "Disable" directs the machine not to use DMA during bi-directional transfers and use a contigous data-stream. 
   The DMA-mode tends to miss backcoming signals from PP-devices especially PP CD-ROMs, Tapes and Zip-Drives. Some printer-drivers use the bi-directional communication to signal details from the printer back to the computer 

Direct Connection under W95
  Yes it does work. I even used the ECP port setting with the parallel cable. Both ports were at Parallel 2, and DMA Arbitration 1. 
  For a detailed description of the DCC process, 95 to 95, 95 to 3.1x, etc. check out Connect Pages at Kime.Net.

Bermuda Planar ADF

Serial Port One: Choices are Serial 1 through Serial 16, or disabled.  Standard interrupt levels are IRQ 4 for serial 1 and IRQ 3 for any other serial level. 

Serial Port Two: Choices are Serial 1 through Serial 16, or disabled.  Standard interrupt levels are IRQ 4 for serial 1 and IRQ 3 for any other serial level. 

Parallel Port: Choices are Parallel 1 through 4 or the port can be disabled. 
NOTE: IBM used a different IO address for LPT1 of 03BC-03BF instead of the common 0378-037B. You may be better off to set your parallel port to PARALLEL 2. 

PARALLEL 1 io 03bch-03bfh 1278h-127bh int 7 
PARALLEL 2 io 0378h-037bh int 7 
PARALLEL 3 io 0278h-027bh int 7 
PARALLEL 4 io 1378h-137bh int 7 

Parallel Port DMA Arbitration Levels: Choices are Shared Level 7 through Shared Level 0, (dedicated) Level 7 through (dedicated Level 0), and Disabled. 
   If the level selected is shared then other devices can be set at the same level.  If the level selected is dedicated then only this device can be set to that level. 

SCSI Address (ID): ID of the built-in SCSI controller. Choices are ID7 through ID0. Under normal circumstances, select <7>. 

SCSI I/O Address: Select: I/O address of the built-in SCSI controller. 
   <3540h-3547h>, 3540h-3547h, 3548h-354Fh, 3550h-3557h, 3558h-355Fh, 3560h-3567h, 3568h-356Fh, 3570h-3577h, 3578h-357Fh 

SCSI Fairness On/Off: Choices are On or Off. Bus Arbitration Fairness controls whether the adapter will release control of the bus when it has been using it exclusively. Under normal circumstances, select <On>. 

SCSI DMA Arbitration Level: Choices are Level 1, 3, 5 through E. Selecting an arbitration level allows only this device to use the value. 

ADP Fields (System determined)
Alternate Processor: Type of processor installed in alternate processor socket on system board. 

Current System Speed: Current speed of the system, 25MHz or 33MHz. 

System Board: System board type 

CPU Upgrades
I bought an Evergreen 586 CPU upgrade with an AMD  P133 chip on it.  It made my PS/2 77 (9577-0UF) go noticably faster, perhaps 15 to 25 percent quicker.  No incompatibility problems - but McAfee Office still rates my machine as a 486-33 (go figure !). 

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