Radio Shack TRS-80 Model II Reference Manual page 131

UTILITY PROGRAMS
During the transmission, incoming text will be displayed on the screen. If the
host program echoes your transmissions, you will be able to verify that the
data was sent accurately.
During the transmissions, you can adjust the delay between characters by
repeatedly pressing the
ill
(faster) and
ill
(slower) keys. If echoed data
appears garbled, slow down the transmissions. If not, you might want to
speed it up.
If a break character or sequence is received in this mode,
TERMINAL
will pause until
the next character is received. IfaX' 13' is received,
TERMINAL
will pause until a
X' 11 " is received. (By convention, X' 13' is called the
DC3
signal and means
pause; X'
11'
is called the
DCl
signal and means resume).
If
transmission errors occur,
TERMINAL
will display a descriptive error
message and wait for the error condition to be corrected. When it is, normal
I/O will resume.
To exit from this mode at any time, press (BREAK) . You will be returned to
the menu.
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