User`s guide

56K Professional Message Modem50
Xmodem
This is the first of a family of
error control
software
protocols
used to
transfer files between modems. These protocols are in the public
domain and are available from many bulletin board services.
XON/XOFF
These are standard
ASCII
control
characters
used to tell an intelligent
device to stop/resume transmitting data.
Ymodem
This is an error-checking
protocol
that can send several files of data at
a time in 1024-
byte
(1K) blocks. This protocol can use either
checksums or CRC for error checking.
Ymodem G
This is similar to
Ymodem
, except it includes no error checking, which
makes it faster.
Zmodem
This is similar to
Xmodem
and
Ymodem
, except it includes batch
transfer, the ability to recover from a partially complete transfer, an
autostart feature, and improved efficiency.