8600 CPU

Outline of IPB CPU Slots

S1 Select Applications Processor (AP) or File Processor (FP)

CPU 1 (FP) connects to four-slot MC (Primarily NICs)
CPU 0 (AP) connects to eight-slot MC (Primarily system  - tape, fax, 3270, etc...)

For a dual CPU system, CPU 1 AP/ FP switch should be for FP.
For a single CPU system, it does not matter how the AP / FP switch is positioned.

The 4 and 8 slot MCA planar is ONE board that plugs into the IPB backplane. You cannot change which CPU Slot connects to which set of MCA slots. The 195 comes with this 4 / 8 slot planar installed, so when you get another CPU Board, you just plug it into the IPB card cage.

In the dual processor 295, the OS/2 HPFS runs on the File Processor, and OS/2 LAN Server and the application(s) run on the Application Processor. The OS/2 kernel and the interprocessor code run on both processors.


IDT 79R3020 Write Buffer
Intel 82311 Peripheral Family
   82303 Local Channel Support Chip
   82304 Local Channel Support Chip
   82307 DMA Controller / Central Arbiter chip
   82308 Micro Channel Bus Controller
   82309 Address Bus Controller
Intel 8742A KBC
D1-3 Diagnostic LEDs (left, low - right, high)
S1 Set CPU Board to AP or FP
S2 CPU board Reset switch. Also on RMP
BATT CR14250SE 3 V / 850 mA battery
74F899QC 9-Bit Latchable Transceiver
DS14C89A Quad CMOS Receiver
DS14C88N QUAD CMOS Line Driver
DS1210 NVRAM controller
MB8464A-10L 8Kx8 SRAM
P1 Serial port
P2 Parallel port
Y1 32 KHz xtal

Looks as if the IP board is the same for a DX33 and DX50. The daughtercard connects with a Beam type connector, instead of the pins used in the 8570-Bxx.

Clear CPU Board CMOS

Right next to the watch xtal are two loops, in this case TP2 and TP3.

Remove CPU card from server.
Momentarily short TP2 and TP3, shorting out power to CMOS and erasing settings.

CPU Board Diagnostic LED Codes

The processor module starts up, displaying these codes, in the order seven through zero.

The LEDs are listed as seen from the front of the server. The low-order LED is on the left, towards the side panel. The high-order LED is on the right, toward the system backpanel.

Code LEDs Description
7 O - O - O The processor-module CPU is being held in reset. This can be caused by the RMP, the user pressing the CPU reset button, or the other module’s CPU EBIOS detecting an error on this module. A power-cycle may release the reset. Otherwise, problems with the processor module are indicated.
6 X - O - O Output by EBIOS as soon as the processor module resets. The first processor to boot shows this code only briefly. The second shows this code while waiting for the first to complete POST.
5 O - X - O Indicates that POST is starting.
4 X - X - O POST is running on the module. Any errors encountered are displayed on the server console.
3 O - O - X Second processor to boot only. Second processor has completed POST and is idle. This is the normal state for ref-disk, DOS, and uniprocessor mode.
2 X - O - X Not used.
1 O - X - X Not used.
0 X - X - X Processor-module is operational.
X = OFF, O = ON

EBIOS is a Phoenix Technologies product.

Security Dongle

Parallel port has a security dongle attached.
Rainbow Technologies Sentinel Pro, model 4BNZBH-B

Sentinel Pro drivers - ver. 5.38 DOS, OS2, Win 3.1, Win 9x, NT
Note: File removed. Some engines detect it as a threat. Seems to be a false-positive but Google is not happy about it. You can download ver. 5.39 HERE (FTP).

WBST said:
   The only reference to "protection keys" appears to apply solely to IBM's Orthogonal RAID-5 Disk Array/2. Presumably these keys are to ensure the software is licensed to operate on those CPU boards. The details aren't exactly very clear.

Announcement Letter 292-302
o   IBM Orthogonal RAID-5 Disk Array/2
   -  Hardware security keys must be installed in each system processor.

Sentinel Pro FAQ (source)

Q: The SentinelPro is a non-programmable key, how is my key different from anyone else's?
A: All production units have unique Developer IDs assigned to them.  Each Developer will also get their own algorithm.

Q: How do I know what response I should expect when querying my key?
A: The Proeval utility, in the tools subdirectory of your SentinelPro software installation, can help determine the responses your key will return to a given query. You can also generate a simple program that queries and stores the responses in a query/response table.

Q: Query returns the same response when the key is absent as it does when the key is connected?
A: You may not have initiated the program to communicate to the key. There are two common configurations which you need to keep in mind when you initially query the Pro: Parallel Port Setting, and Family Code setting. The default for these two settings are LPT1 and "BH". If you are using a key on a port other than LPT1, you need to specify this in your code. If you are using any family code other than "BH", you need to make sure that you have set up the family code prior to the first query/response check.

Q: How do I set up the Family Code?
A: Whenever you send in two characters as a query string, it is a command to the driver, and not a true query. To change set up the Family Code for your key, you need to query "3x" to set up the first digit, and "4x" to setup up the second digit ("x" represents the each character of the family code.) For example, if you have a family code of BC, you will set up your code with the following:


Note: The syntax used to pass the query string is slightly different for each high-level language.

Q: How do I know what family code has been assigned to my key?
A: Look on the plastic case of your key. There will be a string of digits and characters that will start with RB-XXXXBH-B. You would look at the last three characters of this key. The two characters before the second dash is the family code. The character after the second dash says that it responds on the BUSY line.

Q: Can SentinelPro keys be cascaded with other SentinelPro keys?
A: Yes. Up to five SentinelPro keys can be attached to the same parallel port at the same time allowing protection for multiple applications. Cascaded SentinelPro keys must have different family codes.

Q: Can SentinelPro keys be cascaded with a non-Rainbow key?
A: If you must attach a non-Rainbow key to the same port, attach the SentinelPro key directly to the port, then attach the other device to the Sentinel Pro.

Intel486 DX CPU-Cache Module [P] (from HERE)

U1 74F377
U2 80486DX-50 CPU
U3-8,10-12 82490DX cache SRAM
U9 82495DX-50 cache controller

Based on the 82495DX / 82490DX Cache-set (slides).

Block Diagram

One 377 latch, a 486DX-50, an 82495DX cache controller, 8x32KB 82490DX cache modules (Data), 1x32KB 82490DX cache module (Parity). Module outline is stylized...


The big heatsink holds down a white silicone heat conductive pad onto the top of the 9 KU82490DX L2 cache chips. The two big chips under heatsinks are a 495 cache controller and a 486DX-50. The heatsink is bonded TIGHTLY to the CPU and cache controller...

Intelligent CPU / Cache Module Removal

If you either disassembled it for fun, or if you got a 486DX-50 module to replace a 486DX-33 module, you can save yourself some pain... DO NOT try to remove the heatsink over the CPU and cache controller. The adhesive is very good...

There are two hex standoffs on the right side of the CPU / Cache module. You must only remove the nut on the reverse side of the IPB board. There is no easy way to tighten the screws holding the module PCB to the hex standoff as they are under the CPU heatsink!

Unscrew the phillips screws by "J1" (lower left corner), upper left (by U11) and center top (to right of U1). Warning! Each screw runs through a ferrule (spacer) so that the heatsink is held snugly, but not bowed down over the cache chips. These ferrules are loose! Disassemble the module on a workbench so when something small falls off, you can find it.

I didn't mention loosening the screw to the lower right corner of U5 (called out with the arrow). Leave this alone until after you pull the CPU/Cache Module up off of J1. You CANNOT reach the nut below the module until the module has been detached from the CPU Board!!!

Note: The phillips screw to the lower right of U5 does not thread into a hex standoff. Instead, there is a rubber washer that is put on the screw below the module PCB and the nut is then tightened up against the rubber washer. Do not fasten the no-hex screw without the washer....

Re-Assembly of Heatsink onto CPU-Cache Module
The cache chip heatsink on the left is held in with those countersunk head phillips screws, and the heatsink rests on four small ferrules that are loose. BUT you need to tighten up that screw between U5 and J1 (using a rubber washer below the daughtercard) before mounting the daughtercard, because that captive tooth washer nut is TOTALLY inaccessible once you plug the cache card on... TOTALLY.

Processor Configurations

8600-001 – 486DX-33 w/128KB L2 , 486DX-50, w/256KB L2.
8600-002 – Two 486DX-50s w/256KB L2 cache. (L2 direct mapped, write-through)
ASMP for OS/2 (one 486 for OS and apps; one 486 for file system and protocols).

Each processor board has a switch on the mounting bracket, AP or FP.
AP - Application Processor. Runs OS/2 programs
FP - File Processor. Performs the file related functions.

Each processor board contains a 486DX processor, along with a Level 2 memory cache, and the attachment to the Micro Channel. There are two Micro Channels, one with four slots, and the other with eight slots. The processor in slot 0 is always connected to the eight-slot Micro Channel, and the processor in slot 1 is always connected to the four-slot Micro Channel.

Configuring the Server 295 for multiprocessor or uniprocessor mode is done using the utility MPSETUP, which is also used for installing Multi Processing Extensions/2 and for allocating memory to the AP and FP processors, and the HPFS cache.

When configured for multi-processor mode, changes are made to the CONFIG.SYS file, and a new CONFIG.FP file is created for the FP processor. However, the utility MPSETUP should always be used to switch between uni-processor and multi-processor modes. It is wise to always return to uni-processor mode before altering the CONFIG.SYS file or upgrading the operating system.

Content created and/or collected by:
Louis F. Ohland, Peter H. Wendt, David L. Beem, William R. Walsh, Tatsuo Sunagawa, Tomáš Slavotínek, Jim Shorney, Tim N. Clarke, Kevin Bowling, and many others.

Ardent Tool of Capitalism is maintained by Tomáš Slavotínek.
Last update: 08 May 2024 - Changelog | About | Legal & Contact