US Robotics 3CP5695, User Manual

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buffer
A temporary memory area used as storage during input and output
operations. An example is the modem's command buffer.
byte
A group of binary digits stored and operated upon as a unit. Most often
the term refers to 8-bit units or characters. One kilobyte (KB) is equal to
1,024 bytes or characters; 640 KB is equal to 655,360 bytes or
characters.
carrier
The basic signal altered or modulated by the modem in order to carry
information.
character
A representation, coded in binary digits, of a letter, number, or other
symbol.
characters per second (cps)
A data transfer rate generally estimated from the bit rate and the
character length. For example, at 2400 bps, 8-bit characters with
start/stop bits (for a total of ten bits per character) will be transmitted at a
rate of approximately 240 characters per second (cps). Some protocols,
such as error-control protocols, employ advanced techniques such as
longer transmission frames and data compression to increase cps.
class 1 and 2.0
International standards used by fax application programs and faxmodems
for sending and receiving faxes.
cyclic redundancy checking (CRC)
An error-detection technique consisting of a test performed on each
block or frame of data by both sending and receiving modems. The
sending modem inserts the results of its tests in each data block in the
form of a CRC code. The receiving modem compares its results with the
received CRC code and responds with either a positive or negative
acknowledgment.