OB1 Virtual TCU OB2 RSCS Virtual Virtual Machine TCU OB3 Virtual TCU
191 009 ;,........--- -- Virtual RSCS Console
System "-. Disk Figure 1. RSCS Virtual !acbine Configuration
Locations and Links
At a local installation there are
remote stations. A unique location
each of these remote stations.
a number of transmission paths to
identifier (locid) is assigned to
For each transmission path (nonsvitched line) or potential
transmission path (switched line), a link must be defined at the local VM/370 installation. Each such link is given a name (linkid) that
defines the location identifier of the remote station to which transmission Fath leads. This link can be defined either at system generation cr by means of the DEFINE command. REMOTE STATIONS Remote stations are configurations of I/O devices attached to the VM/370 computer by binary synchronous (ESC) switched or nonsvitched lines. Two
types of re.cte stations are supported by RSCS: program.able remote
stations and nonprogrammable remote stations.
Programmable remote stations, such as the IEM and System/370, are IBM processing systems with attached binary synchronous
communicaticns adapters. These systems must be programmed to provide the
3-4 IBM VM/370: System Logic and Problem Determination--Volume 3

MULTI-LEAVING line protocol necessary for their devices to function as
remote stations. This programming support is provided by a remote
ter.inal processor (RTP) program generated according to HASP workstaticn
protocol and tailored to the system's hardware configuration. Certain
programmable remote stations like the System/3 can only be programmed to
function as remote terminals. Others, like the System/360 and System/370, can function either as reaote terminals or as host batch
systems using Rses as a remote job entry workstation= Both of these
types of remote stations are managed by the spool MULTI-LEAVING (SML) line driver of RSCS. Bonprogrammable remote stations are I/O configurations that cannot be
programmed, but are hard-wired to provide the line protocol necessary
for them to function as remote stations. They can receive, read, print,
punch, and send files. An examFle of a nonprogrammable remote staticn
is a 2780 Data Tratismission Terminal. Nonprogrammable remote staticns
are managed by the NPT (Nonprogrammable Terminal) RSCS line driver.
The tYFes of devices supported for all types of remote stations,
programmable and nonprogrammable, are listed in the VM/370 §y!de. Network Control: RSCS and VM/370 Commands Both RSCS and VM/370 commands are used to control RSCS. The RSCS commands are used to control the RSCS network; VM/370 CP and ClS commands are used by virtual machine users who use the RSCS network. RSCS COMMANDS To manipulate file being transmitted across the network and to
communicate with the various network users, the Rses control program provides a command language. Figure 2 is a list of RSCS commands and
the functions they perform. You can find detailed descriptions of these
commands in the pUblication §EQoling RSCS Introduction 3-5