User`s guide

56K Professional Message Modem 41
asynchronous transmission
Data transmission in which the length of time between transmitted
characters
may vary. Since the time lapses between transmitted
characters are not uniform, the receiving modem must be signaled as to
when the data bits of a character begin and when they end.
The addition of
start/stop bits
to each character serves this purpose.
auto answer
In this setting the modem can pick up the phone line when it detects a
certain number of rings. See S-register S0 in the “Technical Quick
Reference” section.
auto dial
A process where your modem dials a call for you. The dialling process is
initiated by sending an
ATDT
(dial tone) or
ATDP
(dial pulse) command
followed by the telephone number to dial. Auto dial is used to dial voice
numbers. See command
Dn.
baud rate
A term used to measure the speed of an analogue transmission from
one point to another. Although not technically accurate, baud rate is
commonly used to mean
bit rate
.
binary digit
A 0 or 1, reflecting the use of the binary numbering system. It is used
because the computer recognizes either of two states, OFF or ON. The
shortened form of binary digit is bit.
bit rate
This refers to the number of
binary digits
, or bits, transmitted per
second (
bps
). It is also referred to as transmission rate.
Communications channels using telephone channel modems are
established at set bit rates, commonly 2400, 4800, 9600, 14,400, 28,800
and higher.
bits per second (bps)
This is the bits (
binary digits
) per second rate. Thousands of bits per
second are expressed as kilobits per second or kbps.