IBM System/370 Guide

2
CPU retry of most failing CPU hardware operations is handled
automatically by the hardware without programming assistance.
Writable control storage (WCS) is included in addition to read-
only storage (ROS) to contain new Model 165 instructions, emulator
microcode, and CPU diagnostics.
• Relocatable emulators are provided that operate under OS control.
Concurrent execution of System/370 programs with 7000-series
programs is supported. A 7080, a 7070/7074, and a
709/7090/7094/709411 emulator are available on a mutually exclusive
basis.
• A free-standing 3066 System Console is required. Its features are:
A buffered cathode ray tube and an alphameric keyboard for rapid
operator/system communication
An indicator viewer to display system status
A system activity monitor to provide, via the system activity
meter, visual display of average system activity
A microfiche document viewer for CE use
A processor storage configuration plugboard
A device for loading WCS and diagnostic routines
• Channel features of the Model 165 are as follows:
2870 Multiplexer Channels, 2860 Selector Channels, and the new
2880 Block Multiplexer Channels can be attached - for a total of
seven addressable channels. A single 2880 channel can operate
at a 3 MB rate with attachment of an optional feature.
The Extended Channels feature permits a Model 165 to have up to
twelve addressable channels, which can support an aggregate channel
data rate in excess of nine megabytes per second.
The 2880 Block Multiplexer Channel is a superset of the 2860
Selector Channel. When used in conjunction with rotational position
sensing devices, it can increase total system throughput by
permitting more data to enter and leave the system in a given time
period than can the 2860. A single 2880 channel can support
interleaved, concurrent execution of multiple high-speed I/O
operations.
Channel retry data is provided after channel errors so that error
recovery routines can retry I/O operations.
• storage features offered by the Model 165 are as follows:
A two-level memory system, consisting of fast, large-size processor
(main) storage used as backing storage for a smaller, very high-
speed buffer storage, is implemented. The CPU works mostly with
the buffer so that the effective access time for data is reduced
to a fraction of the processor storage cycle time.
8K or 16K bytes of SO-nanosecond monolithic buffer storage is
available (SK is standard). The CPU can initiate a request
for eight bytes from the buffer every 80 nanoseconds.

IBM System/370 Specifications

General

Brand	IBM
Model	System/370
Category	Server
Language	English