Black Box MD1276A, User Manual

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topic. Often SIGs set up bulletin boards, available only to SIG members.
Simplex
Data communications in one direction only.
Single-Digit Keying
Refers to videotex systems where you only need to press one numeric key from an index. See
also Double-Digit Keying.
Software
Computer program or set of computer programs held in storage, and loaded into RAM for
execution.
Software Downloading
Known as software downloading or teleloading on videotex systems and downloading on some
bulletin boards. Refers to the transferring of software from a remote system to your computer.
Software Handshaking
A method of controlling the flow of data between two computers or terminals. Special control
characters are sent from one terminal to the other in order to halt or re-commence the flow of
data. See also Hardware Handshaking.
SOH
Start Of Header used in synchronous transmissions indicating the start of a header block.
Space
One of the two possible states of a binary data element. The open circuit condition in a
teleprinter circuit. Also see Mark.
Special Interest Group
See SIG.
Start Bit
When a character is transmitted asynchronously to another computer, a start bit always
precedes the actual data. Seven or eight data bits, an optional parity bit and a stop bit will
follow.
Stop Bit
The last bit or element transmitted in asynchronous transmission of a character to return the
circuit to an idle state. One or two stop bits are sent at the end of each character of data.
STX
Start Of Text control character used in synchronous transmission which precedes the text