7552 Common Devices

Early 7552 Keyboard Pinout
Digital Output

Model 040 processor.
Model 140 processor, 720K diskette and 10Mb HD
Model 540 processor, 720K diskette (1.44MB option), one 20Mb HD
   10, 20, or 42MB HDs will interchange between all GEARBOX that have a DASD module.

This is the little brother of the 7568 GEARBOX 800. It shares the same case and shroud setup.


This box was also OEM'd for Allen-Bradley as the 6122.
1784-KT2/B Communication Interface Module (60C6.ADF)
1784-KT2/C Communication Interface Module

The 1784-KT2 Communication Interface Module can be inserted into any 8- or 16-bit MCA expansion slot. The 1784-KT2 : makes your PS/2 computer an active node on Data Highway Plus provides single cable connection to a PLC-2, - 3, or -5 family programmable controller operates with 6200 programming software when combined with Allen-Bradley 6001-F1E2 software, allows you to create your own custom interface to Data Highway Plus.

The 1784-KT2 has been verified for the following computers:
Allen-Bradley 6123, 6124
IBM PS/2 7541, 7561, 8550, 8555, 8560, 8570, 8580

6123/6124 User's Manual (publication 6123-2.1) (DEAD)

The following sections provide directions for connecting a 1784-KT2 to a PLC-2, PLC-3, or PLC-5.

Required Cables for Connecting to a Programmable Controller:

Use this cable When connecting to
1784-CP2 PLC-2 Family Programmable Controllers
1784-CP3 PLC-3 Family Programmable Controllers
1784-CP PLC-5 Family Programmable Controllers
1784-CP6 PLC-5/40 and PLC-5/60 Programmable Controllers (pub 1784-2.26)
1784-CP7 Adapter
w/ 1784-CP Cable
PLC-5/40 and PLC-5/60 Programmable Controllers (pub 1784-2.29)

Computer Oddity 2001

David Bowman says:
   I've got it too boot, used a screwdriver to bypass that "locked" keyboard feature. It runs to a screen telling me to hit F1 to continue (looks like the Setup feature might be bios based?).

Early 7552 Keyboard Pinout

4+5v Detect
5-KB Detect
RingShield Gnd

The only problem so far is the lack of a Keyboard, or at least a suitable one.  Its the size of an AT keyboard, but one of the pins is in the middle of the DIN.  I didn't see a keyboard and not till it was too late to go looking for the original, noticed this particular port.  I hope IBM's done this before and the pinout is known and a standard keyboard CAN be fitted to this one
   Keyboard offers separate typewriter and numeric keypads. Depending on the application program, from 10 to 40 special function keys may be supported.  The keyboard is attached to the 7552 via a 12-foot coiled cable, permitting a variety of workspace configurations.
 (Ed. The late models used a "standard" keyboard, either AT or PS/2)
   When the 7552 is configured without diskette, keyboard, or display, an IBM 5531, 7531 or 7532 Industrial Computer or another 7552 configured with a diskette, keyboard, or display is required as a remote terminal to load programs and to provide an operator interface for the 7552.  A Remote Terminal Interface (#6078) is required in the 5531, 7531, 7532, or other 7552 to provide an interface to the 7552 through its keyboard port.  IBM program product 5601-053 provides program utilities to support the remote terminal interface functions.

   It does have what appears to be a card slotted in with a 9 pin monitor
output and 2 composite outputs (assuming its video)   (Ed. EGA?)

Digital Output

Pin Function Pin Function
1 +DO1 9 -DO1
2 Reserved 10 Reserved
3 +DO2 11 -DO2
4 Reserved 12 Reserved
5 +DO3 13 -DO3
6 Reserved 14 Reserved
7 Reserved 15 Reserved
8 Reserved

Data Output Point Circuit

These points are optically isolated. They are active "on" or "closed" opto-coupled outputs. Each point is capable of switching a voltage source of 5 to 30 Vdc at 30mA load. The voltage drop across the DO point depends on the load, but is typically about 0.8v.
   The DO points are driven by a Texas Instruments TIL157A Optocoupler, with an input- diode forward current of 15mA.

Data Output BIOS Function Calls are HERE

The 7552 Industrial Computer is based on a high-performance, 16/24
bit, 10 MHz Intel 80286 microprocessor, and 512Kb of memory standard.
System memory may be further expanded with memory card and 512Kb memory options. Up to 3Mb of optional memory can be added.
170 watt power supply, two cooling fans.

IBM PC FEATURE ADAPTER (#6077): One required for each IBM PC feature adapter to be plugged in the 7552. It provides an interposing card and other hardware to mount the IBM PC feature card in the 7552 card shroud. (Ed. Yes, this is the mythical ISA card interposer foretold of by Brother Tony)

Floor standing feature (#6098) or a rack mount feature (#6097) can be purchased. The floor standing feature provides all necessary hardware to mount the 7552 in the floor standing position and provision to bolt the system unit to the floor. The rack mount feature provides all necessary hardware to mount the keyboard in a standard 19" rack. The rack and/or panel mount hardware for the system unit is a standard component of the 7552 and is shipped with the system.

MEMORY ADAPTER (#6074): Permits the addition of up to 3Mb of memory. The first 512Kb increment of memory is included with this adapter and five 512Kb Memory Expansions (#6075) can be added, for a total of 3Mb of additional memory.
512K MEMORY EXPANSION (#6075): Each #6075 adds 512Kb of memory to the Memory Adapter (#6074). Maximum: Five.

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Ardent Tool of Capitalism - MAD Edition! is maintained by Tomáš Slavotínek.
Last update: 11 Apr 2021 - Changes & Credits | Legal Info & Contact