IBM RS/6000 - Manual (Page 52)

X.21 (not switched) up to 64 Kbps
Each feature is selected by the cable, which can be ordered in 3m (9 foot) or 6m
(18 foot) length. These are the main characteristics for this adapter:
Code resident on the adapter off-loads low-level X.25 tasks from the system
processor
512 KB RAM for buffering
Synchronous protocols can be supported
Automatic recognition of the selected interface cable
Capacity of concurrent support up to 250 virtual channels
Requires one ISA slot
Maximum of three adapters of this type can be installed
Installation and configuration of this adapter is not automatically made by AIX;
proper operations must be followed by the system manager. The DIP switches on
the adapter must be set correctly before configuring the adapter to the AIX
operating system. 6.7, “X.25 Interface Co-Processor ISA Adapter (FC 2961)” on
page 120 explains how to install and configure this adapter.
ISA 4-Port Multiprotocol Communication Controller (feature #2701)
This adapter supports the attachment to wide area networks at speeds up to 64
Kbps. This adapter consists of a base card and daughter card. The two cards are
physically connected and require a single ISA bus card slot.
This adapter can support four different physical interfaces by using a IBM 4-Port
Multiprotocol Interface Cable (feature #2705). This cable is actually a breakout box
featuring four ports that support EIA-232, EIA-422A, V.35, and X.21 physical
interfaces.
The main characteristics for this adapter are:
80C186 @ 10 MHz processor
1 MB RAM for data buffering
Synchronous protocols
EIA232, EIA422A, V.35, and X.21 physical interfaces supported
Requires one ISA slot
Maximum of three adapters of this type can be installed
Installation and configuration of this adapter is not automatically made by AIX;
proper operations must be followed by the system manager. DIP switches on the
adapter must be set correctly before configuring the adapter to the AIX operating
system. 6.6, “4-Port Multi-Protocol ISA Adapter (FC 2701)” on page 115 explains
how to install and configure this adapter.
ISA 8-Port Asynchronous Adapter (feature #2931)
This adapter is used to connect up to eight EIA-232 asynchronous serial devices
(terminals, modem, printers, and so on). This feature provides both the adapter
28 Introduction to PCI-Based RS/6000 Servers