G
LOSSARY
11
serial transmission
The transfer of data characters one bit at a time, sequentially, using a
single electrical path. See Parallel Transmission.
software flow
control
A form of flow control that uses XON and XOFF characters to start and
stop the flow of data.
start bit
The signaling bit attached to the beginning of each character before
characters are transmitted during Asynchronous Transmission.
stop bit
The signaling bit attached to the end of each character before
characters are transmitted during Asynchronous Transmission.
SDLC
See Synchronous Data Link Control
S-register
An area of NVRAM that is used to store a setting.
switch
See central office switch.
Synchronous Data
Link Control (SDLC)
A protocol developed by IBM for software applications and
communicating devices operating in IBM's Systems Network
Architecture (SNA). The protocol defines operations at the link level of
communications, for example, the format of data frames exchange
between modems over a phone line. See BISYNC, Protocol, HDLC.
synchronous transmission
A form of transmission in which blocks of data are sent at strictly timed
intervals. Because the timing is uniform, no Start or Stop bits are
required. Compare Asynchronous Transmission.
Some mainframes only support synchronous communications unless
their owners have installed a synchronous adapter and appropriate
software.
terminal
A device whose keyboard and display are used for sending and
receiving data over a communications link. Differs from a
microcomputer in that it has no internal processing capabilities. Used to
enter data into or retrieve processed data from a system or network.
terminal mode
An operational mode required for microcomputers to transmit data. In
Terminal mode the computer acts as if it were a standard terminal such
as a teletypewriter, rather than a data processor. Keyboard entries go
directly to the modem, whether the entry is a modem command or
data to be transmitted over the phone lines. Received data is output
directly to the screen. The more popular communications software
Summary of Contents for Courier
Page 12: ......
Page 28: ...1 14 CHAPTER 1 CONNECTING TO YOUR ISP ...
Page 36: ...3 4 CHAPTER 3 UPGRADING YOUR MODEM ...
Page 58: ...6 6 CHAPTER 6 WORKING WITH MEMORY ...
Page 64: ...8 4 CHAPTER 8 CONTROLLING EIA 232 SIGNALING ...
Page 72: ...9 8 CHAPTER 9 ACCESSING AND CONFIGURING THE COURIER V EVERYTHING MODEM REMOTELY ...
Page 80: ...10 8 CHAPTER 10 CONTROLLING DATA RATES ...
Page 96: ...12 6 CHAPTER 12 FLOW CONTROL ...
Page 108: ...13 12 CHAPTER 13 HANDSHAKING ERROR CONTROL DATA COMPRESSION AND THROUGHPUT ...
Page 112: ...14 4 CHAPTER 14 DISPLAYING QUERYING AND HELP SCREENS ...
Page 122: ...15 10 CHAPTER 15 TESTING THE CONNECTION ...
Page 142: ...17 8 CHAPTER 17 TROUBLESHOOTING ...
Page 156: ...A 14 APPENDIX A S REGISTERS ...
Page 172: ...B 16 APPENDIX B ALPHABETIC COMMAND SUMMARY ...
Page 178: ...C 6 APPENDIX C FLOW CONTROL TEMPLATE ...
Page 186: ...E 4 APPENDIX E V 25 BIS REFERENCE ...