Table IV. Meter Operation under Various TPS Conditions Switch Position TPS State :--' CPU 1 CPU 2
Neutral ON ON CPU 1 attached CPU 2 attached OFF ON Neutral CPU 2 attached ON OFF Neutral CPU 1 attached OFF OFF Neutral I NOTES:
1. Metering-In. Metering-In is a line from all
attached control units and is used to condition
the CPU meter for operation. The Metering­
In signal originates from each I/O device and/
or control unit and is generated by the device
from the time of acceptance of a command un­
til the generation of Device End for that com­
mand.
Meter is Running when
Metering Out is Active for CPU 1, or CPU 2 CPU 1 only CPU 2 only CPU 2 only CPU 2 only CPU 1 only CPU 1 only
Meter is neyer active
regardless of Metering Out I from either CPU 1 or CPU 2.
2. Metering-Out. Metering-Out is a line from
the channel to all attached control units and is
used to condition all meters in assignable
units and I/O units. Metering-Out is raised
whenever the CPU meter is recording time.
67

APPENDIX B. COMMUNICATIONS FACILITIES
The 2703 operates in half-duplex mode over: • Common-carrier switched telephone network. • Common-carrier switched 150-baud Teletype­
writer Exchange (TWX) network • Common-carrier leased private-line telephone
service • Common-carrier leased private-line telegraph
service
a. Common-carrier Type 1002 and 1005 pri vate-line service
b. 150-baud Type 1006 pri vate -line service • Western Union Type 3002 channels with C1
conditioning • Western Union Type 3002 channels with C2
conditioning • World Trade Common-Carrier Private Line
Telegraph Circuits (Single Current and/or
Double Current) • Equivalent privately owned communications
facilities COMMON -CARRIER - PROVIDED FACILITIES
Common-Carrier Switched Telephone Network
1. At 134. 5 bps, a Western Electric Data Set 103A2* is required for each line equipped to
answer calls from asynchronous terminal
devices.
2. At 1200 bps, a Western Electric Data Set 202C1, * or a combination of a 202D1 * with a
Data Auxiliary Set 804A1, * is required for
each line equipped to answer calls from synch­
ronous terminal devices.
3. At 2000 bps, a Western Electric Data Set 201A3* is required for each line equipped to
answer calls from synchronous terminal
devices.
4. For each line arranged to automatically ori­
ginate calls, a Western Electric Automatic
Calling Unit 801A1 * or 801C2* is required in
addition to the data sets in items 1, 2, and 3. 5. For World Trade switched networks operating
at bit rates up to 600 bps, an IBM 3976 Model
2 is required.
6. For Binary Synchronous Communications at
speeds of 600 or 1200 bps on World Trade
*or equivalent
68
switched networks, each line requires one
of the following:
a. IBM 3976 Model 3 Modem for use in
countries where approved.
b. GPO Date 1 1 1\Todel 5 for use in the
United Kingdom.
c. PTT D1200S (GH 2011 Model 5) for
use in Germany.
d. PTT GH 2002A for use in Sweden. NOTE: Automatic answering is available on each of the data
sets above.
Common-Carrier Switched Teletypewriter Exchange (TWX) Networks
1. For communications with common-carrier TWX stations (Model 33/35 type) at 110 bps,
a Western Electric Data Auxiliary Set 811B1 *
is required on each line equipped to answer
calls. NOTE: A common-carrier TWX station must be provided with the
first 811B1* unit ;t each site.
2. For communications with start/stop terminal
devices at 134.5 bps, a Western Electric Data Set 103A1 * is required on each line equipped
to answer calls.
3. In items 1 and 2 preceding, on lines equipped
to automatically originate calls, a Western Electric Automatic Calling Unit 801A1/ A6* or
801C2/C4* is also required for'each line.
Common-Carrier Leased Private-Line Telephone Service 1. At 134.5 bps, either a suitable IBM Line
Adapter, an IBM 2711 Line Adapter Unit equipped with a suitable IBM Line Adapter, or
a Western Electric Data Set 103F2* is required
for each line (see "Note"). World Trade
requires the IBM 3976 Modell modem.
2. At 600 bps (start/stop four-wire), either a 2711
equipped with a suitable IBM Line Adapter or
a Western Electric Data Set 202D1 * is required
for each line (see "Note"). World Trade
requires either an IBM 3976 Model 3 or an IBM
3977 Modell or 2.
3. When connecting to a 2712 Remote Multiplexer
Modell, a four-wire full-duplex Type 3002 Pri vate- Line Service with C2 conditioning and
a Western Electric Data Set 202D2* are re­
quired; when connecting to a 2712 1\Todel 2, a