ELSA TanGo 1000, Руководство пользователя

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Appendix: Glossary
ELSA TanGo 1000
Operating Manual © 1997 ELSA GmbH
37
D Glossary
1TR6 1TR6
is a specification by the German Telekom for ISDN terminal devices with S
0
interface. This specification defines the
→
D channel protocol and is used mainly in
Germany. Most other European countries use the
→
DSS1 protocol.
5ESS 5ESS
is a US standard for the ISDN
→
D channel protocol developed by AT&T. It is a
preliminary standard to the National ISDN-1 standard (
→
NI-1).
Asynchronous transmission
In serial data transmission a method is needed to synchronize
transmitter and receiver in order to enable the receiver to detect the beginning and
end of a transmitted character. In
asynchronous transmission
this structuring is
achieved by marking each byte to be sent with one start bit and one or two stop bits.
Especially in the microcomputer sector, this start/stop method is one of the most
commonly used transmission methods, since, unlike
→
synchronous transmission, it
is comparatively easy to perform.
AT command set
The extended
AT command set
(AT = command prefix
AT tention
) has
become a world-wide standard for the syntax of
→
modem control commands. To
give data communications users the possibility to maintain their familiar command
interface when changing over to ISDN, ELSA
MicroLink
® ISDN products can be
controlled with AT commands as well.
B channel
→
Data channel
Basic Rate Interface
ISDN terminal connector providing two
→
data channels (64,000 bps each)
and one
→
control channel (16,000 bps). The link between the Basic Rate Interface
and the terminal device is the
→
S
0
bus.
Baud Baud
(abbreviation: Bd) is the unit for the step rate (1 Bd = 1 step per second), i.e.
the frequency of status changes on a transmission channel per second. Erroneously,
the unit Baud is often confused with the transmission rate measured in
→
bps. In
the case of signals having only two states (as in the ISDN), the step rate is identical
with the transmission rate.
CAPI C ommon ISDN API
(
API
=
A pplication P rogramming I nterface
). This is a software
interface developed by German ISDN adapter manufacturers in cooperation with the
German FTZ, which is used for communication between ISDN adapters and ISDN
application software.
CCITT
→
ITU-T
Communications
In order to access
MicroLink ISDN/TLpro
from a personal computer, for
software
example to choose transmission parameters or to start a data transfer(
→
Download,
→
Upload), a suitable
communications software
, also called
terminal
program
, is needed. Such a program emulates an "intelligent terminal" on the PC,
i.e. a simple input/output device equipped with additional features for saving
received data and transmitting stored data. All ELSA
MicroLink
®
products
supporting the
→
AT command set are shipped with the communications program
Telix
.