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STATUSI~
INTRODUCTION
This section contains information on how to obtain and
interpret terminal status information. In addition to
terminal status, you can also obtain status information on
input/output devices used with the terminal.
Status requests are made by sending an escape code
sequence to the terminal to select the desired status
information. All status requests are treated as block
transfers. (Refer to Multicharacter Transfers in Section
V). The examples that follow use the DC1 character to
trigger the status transfer (Basic Communication
Protocol).
INTERPRETING STATUS
ASCII
CHARACTER
o
1
2
3
4
5
6
7
8
9
<
>
?
BINARY
0011 0000
0011 0001
0011 0010
0011 0011
0011 0100
0011 0101
0011 0110
0011 0111
0011 1000
0011 1001
0011 1010
0011 1011
0011 1100
0011 1101
0011 1110
0011 1111
In response to status requests the terminal returns an
escape code sequence followed by one or more bytes. The
status bytes are followed by a terminator. The terminator
received may be a CR(LF), RS or GS depending on the
communications protocol and terminal configuration (re-
fer to Section V). The examples that follow use the CR
character as a terminator.
The status information is contained in the lower four bits
of each status byte. The upper four bits of the bytes are set
so that the byte will have the value of an ASCII character.
Each byte can be interpreted as one of 16 characters as
follows:
TERMINAL STATUS
Terminal status is made up of 14 status bytes (bytes 0-13)
containing information such as display memory size,
switch settings, keyboard interface configuration, and
terminal errors. There are two terminal status requests,
primary and secondary. Each returns a set of 7 status
bytes. The terminal status bytes are shown on pages 6-3
and 6-5.
6-1
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