User manual US ROBOTICS 001171-00

[. . . ] User's Guide SPORTSTER VOICE 33. 600 and 28. 800 Faxmodem U. S. Robotics logo are registered trademarks of U. S. Any trademarks, trade names, service marks, or service names owned or registered by any other company and used in this manual are the property of their respective companies. © 1996 by U. S. 7770 North Frontage Road Skokie, IL 60077-2690 All Rights Reserved This manual covers installation and operating instructions for the following U. S. [. . . ] Binary Digit A 0 or 1, reflecting the use of the binary numbering system (only two digits). Used because the computer recognizes either of two states, OFF or ON. Bit Rate Also referred to as transmission rate. The number of binary digits, or bits, transmitted per second (bps). Communications channels using telephone channel modems are established at set bit rates, commonly 300, 1200, 2400, 4800, 9600, 14. 400 and higher. Bits Per Second (BPS) The bits (binary digits) per second rate. Thousands of bits per second are expressed as kilobits per second or kbps. Buffer A memory area used as temporary storage during input and output operations. An example is the modem's command buffer. 24 Byte A group of binary digits stored and operated upon as a unit. A byte may have a coded value equal to a character in the ASCII code (letters, numbers) or have some other value meaningful to the computer. In user documentation, the term usually refers to 8-bit units or characters. 1 kilobyte (Kbyte) is equal to 1. 024 bytes or characters; 640 Kbytes indicates 655. 360 bytes or characters. Carrier A tone signifying a connection the modem can alter to communicate data across telephone lines. 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 and 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 between facsimile application programs and facsimile modems for sending and receiving faxes. Cyclic Redundancy Checking (CRC) An error-detection technique consisting of a cyclic algorithm performed on each block or frame of data by both sending and receiving modems. The sending modem inserts the results of its computation 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. Data Communications A type of communications in which computers are able to exchange data over an electronic medium. 25 Data Compression Table A table containing values assigned for each character during a call under MNP5 data compression. [. . . ] 4 5 6 7 S35-S37 Value 1 2 4 8 16 32 64 128 Result Disable 8S-2D trellis Disable 16S-4D trellis Disable 32S-2D trellis Disable 64S-4D trellis Disable non-linear coding. Disable Pre-coding. Reserved. S38 0 Sets an optional delay, in seconds, before a forced hang-up and clearing of the Transmit buffer when DTR drops during an ARQ call. This allows time for a remote modem to acknowledge receipt of all transmitted data before it is disconnected. The modem immediately hangs up when DTR drops. [. . . ]