HP 262SA - Page 146

Data Communications
Table
7-6. Control Characters Used in Multipoint Data Transmission{Continued)
ASCII
CONTROL
CODE
CHARACTER
(HEX)
DESCRIPTION
ETB
17
End ofTranmissionBlock. This character isused totell
the receiving station to stop accumulating a block
check character
and that the next character transmit-
ted will be the block check character. The ETB charac-
ter must follow the last character in all text blocks
except the last text block ofa message. The ETB char-
acter is included in the block check character ac-
cumulation. (See the ETX character.)
ETX
03
End ofText. This character must be the last character
of the last (or only) text block in a message. It tells the
receiving station to stop accumulating a block check
character. The ETX
character is included in the block
check character. (See
the ETB character.)
EDT
04
End ofTransmission. When this character is sent or
received by
the terminal, it causes the terminal to
switch to Control mode.
It is sent by the terminal after
sending the last text block of a message to the com-
puter,
in response to a POLL sequence when it has no
data to send, orwhile receiving a block of text which it
has found to be greater than the total buffer size C~Hum
Bu f 5" times ~(Bu f 5 i z e"), as selected on the datacomm
menu. An EOT is sent by the computer following the
last text block in a message to indicate that the com-
puter has no more data to send or when the computer
wants
to abort the communication sequence.
RVI (DLE
<)
103C
Reverse Interrupt. This character is sent by the com-·
puter to acknowledge that the last text block was prop-
erly received (see ACKO and ACKl) and at the same
time to request that the terminal stop sending as soon
as possible. When this character is received by the
terminal, the terminal will immediately send an EDT
to the computer. The terminal sends the RVI sequence
when
in Text-In mode and the. key is pressed. This
indicates that the terminal properly received the last
text block but requests the computer to stop sending
text as soon as possible.
7-34