@8F70.ADF - IBM RIC Portmaster Adapter/A 
C8F70.ADF - Init file for @8F70.ADF
rrcm204.txt  Realtime Control Microcode (RCM) V2.04 (portmaster and Multiport model 2)
rrcm204o.exe  Realtime Control Microcode (RCM) V2.04 OS/2
rrcm204d.exe   Realtime Control Microcode (RCM) V2.04 DOS
rcm204a.tar.z   Realtime Control Microcode (RCM) V2.04 AIX
Realtime Interface Co-Processor C Language Support README

m39h8070.exe  Option disk for ARTIC Portmaster (53F2601, -04, -07).
189-169  Realtime Interface Co-Processor Portmaster & Related Features
ZG89-0239 Realtime Interface Co-Processor Portmaster & Related
ARTIC Multiport Model 2 & Portmaster Electrical Interface Board Developer's Guide, 2d Ed, Aug 1996 (HTML, ~210 KB)
ARTIC Portmaster Hardware Technical Reference, 2d Ed, April, 1995 (HTML, ~565 KB)

qCF SOFTWARE FOR ARTIC Quadron's qCF is a C-language software development and enhanced runtime support package for ARTIC communication cards
ARTIC Portmaster (Quadron site)

Portmaster
8 Port RS232 Interface Card

  Shocking news, but the maker and model of the Dsub-78 is ITT, 2DD100SBR-1

Eight Port RS-232 Interface Board/A
The Realtime Interface Co-Processor Eight Port RS-232 Interface Board/A provides the appropriate drivers and receivers to support eight serial I/O ports of RS-232-D/CCITT V.24. Protocols for these electrical interfaces are user programmable. The interface board attaches to the Portmaster Adapter/A and includes a 100 pin connector for external communication. Asynchronous or synchronous modes may be individually selected for each of the eight ports. All ports are supported at up to 38.4K bps full-duplex running concurrently. Actual
performance may vary depending on the users application.

Portmaster 4 Port Selectable EIB P/N 53F2616  FRU 84F7540

Eight Port RS-422 Interface Board/A
The Eight Port RS-422 Interface Board/A provides the appropriate drivers and receivers to support eight serial I/O ports of RS-422-A at indoor cable lengths up to 122 meters (400 feet) or cable lengths up to 1220 meters (4000 feet) with surge protection. (For Outdoor cabling considerations, consult the IBM Physical Planning Instruction Manual for surge protection). Up to two of these ports may be defined as CCITT X.21. Protocols for these electrical interfaces are user programmable. The interface board attaches to the Portmaster Adapter/A and includes a 100 pin connector for external communication. Asynchronous or synchronous modes may be individually selected for each of the eight ports. The following full-duplex data rates are supported by Realtime Interface Co-Processor Portmaster Adapter/A using this interface board. 

* One RS-422-A port running alone
o synchronous using external clocking at 2.048M bps
o asynchronous using internal clocking at 115.2K bps
* Eight ports running concurrently
o synchronous using external clocking at 64K bps
o synchronous using internal DPLL clocking at 57.6K bps
o asynchronous using internal clocking at 57.6K bps
Actual performance may vary depending on the users application.

The Portmaster Adapter/A adapter can be installed as follows:
* 8550 and 8570 and 8573 P75 - up to 2 adapters per system unit
* 8555 - 1 adapter per system unit
* 8560, 8565 and 8580 - up to 4 adapters per system unit
* 8590 - up to 3 adapters per system unit (*)
* 8595 - up to 6 adapters per system unit (*)
* 7541,7542 and 7546 - up to 3 adapters per system unit
* 7561 and 7562 - up to 4 adapters per system unit
* 7568 - up to 6 adapters per system unit 

Note: Adapter limitations per unit are dependent on power requirements of other adapters. 

(*) To support 6 cards in a model 95, the SCSI card must be moved from slot 1 to slot 8. To support 3 cards in a model 90, the SCSI card must be moved from slot 1 to 4. In other words, a Portmaster card in a model 95 can not be installed in slot 8 and for a model 90 in slot 4.

Eight Port Cable 53F2619
The Realtime Interface Co-Processor Eight Port Cable is used in conjunction with either the 8-Port RS-232 or 8-Port RS-422 Interface Boards. The cable connects a 100-pin connector on the Interface Board to eight 25-pin connectors (RS-232-D/CCITT V.24/ISO 2110 standard) housed in a molded block at the end of this cable. 

Surge Protection Adapter 53F2625
The Realtime Interface Co-Processor Surge Protection Adapter can be used to provide voltage suppression circuitry in conjunction with the Eight Port RS-422 Interface Board/A and Eight Port Cable for each port. A Surge Protector Adapter is necessary for each port when its individual cable run exceeds 122 meters (400 feet) in length or is used in conjunction with outdoor cabling. This adapter is usable for asynchronous communications only. This adapter consists of two 25-pin connectors connected by the appropriate surge protection circuitry.

@8F70H IBM Realtime Interface Co-processor Portmaster Adapter/A

Physical Card Number & I/O Address
    The physical card number defines the I/O address  range of the IBM Realtime Interface Co-processor Portmaster Adapter/A. The Physical Card Number determines the Card Base Address; however, the physical card number does not necessarily correspond with the logical card number. For example, the card in the first slot may be given any physical card number, but it will always be considered logical card 0.  The preferred card number/address range is the lowest available.
  <Card 0; 02A0H-02A7H>, Card 1; 06A0H-06A7H, Card 2; 0AA0H-0AA7H, Card 3; 0EA0H-0EA7H, Card 4; 12A0H-12A7H, Card 5; 16A0H-16A7H, Card 6; 1AA0H-1AA7H, Card 7; 1EA0H-1EA7H

Interrupt Level
   The interrupt level is the prioritized interrupt request line on which the IBM Realtime Interface Co-processor Portmaster Adapter/A will interrupt the Personal System 2.  The interrupt priorities are as follows (greatest priority first): 9, 10, 11, 12, 3, 4, 7. The interrupt level may be shared with another adapter. The preferred interrupt level is 7.
  <"Level  7">, 3, 4, 9, 10, 11, 12

Bus Master Arbitration Level
   Arbitration level for the IBM Realtime Interface Co-processor Portmaster Adapter/A Busmaster DMA transfers.

   <"Level E">, D, C, B, A, 9, 8

Fairness
   Enable or disable Fairness feature of the IBM Realtime Interface Co-processor Portmaster Adapter/A busmaster DMA tranfers. This field should normally be Enabled."

  <"Enabled ">, Disabled

Shared Storage Window Location & Size
   The Shared Storage Window is an unused ROM or RAM address range that is used as a window into the RAM on the IBM Realtime Interface Co-processor Portmaster Adapter/A.
   The 'Above 16M, Window=Memory Size' option will allocate a window equal in size to the amount of RAM installed on the adapter, and located at the highest available space between 1G and 4G.  This option will only work if the adapter is installed in a slot which supports 32 bit addressing."

8K Window, Below 1MB

  <"DE000H-DFFFFH, 8K Window (Page 6FH)>, DC000H-DDFFFH (6EH), DA000H-DBFFFH (6DH), D8000H-D9FFFH (6CH), D6000H-D7FFFH (6BH), D4000H-D5FFFH (6AH), D2000H-D3FFFH (69H)

And there are many more choices where these came from.