HP 271308 Technical Reference Manual page 79

HP 27130B
Quoting Character Mode Option
When the Quoting Character Mode option is enabled, the editing characters (backspace and line delete)
and a specific single text terminator are able to be treated literally by preceding them with the
backslash
("\11).
For example, if you type
\ DEL
DEL is put in the user's read buffer, and the line would not be deleted. You would be able to erase the
"DEL" character as any other character typed, even though the echoing of'such an erasure may not
look right on the terminal.
If followed by any other character, the quoting character causes no special action and is placed in the
text buffer as is any other character.
The quoting character and the specific single text terminator are programmable and have a default
value of the backslash (\) character.
Conditional Output Separators Appendage
When the Conditional Output Separators Appendage option is enabled, the firmware will examine
every outgoing character for the user-specified record separator, which has a default value of the
linefeed character. If the user-supplied record separator is found, the firmware sends the output
separators in place of the record separator.
If the Automatic Output Separators Appendage option
IS
enabled, the output separators are also
added to the end of each message.
Speed Sense Mode
The Speed Sense mode, initiated by Control Card (CC) Subfunction 6, puts the card in a mode where
the baud rate of incoming data is sensed and the channel configured accordingly. The firmware waits
for a "start bit" and, in synchronous mode, samples the incoming data stream at 19200 baud. The
resulting data are compared to known configurations of the 7-bit "carriage return ll character (00 hex).
If a match is discovered, the channel is configured for that baud rate, and an event is generated to in-
form the host of the baud rate and the state of the parity bit (the sense of bit position 8). Searching
continues either until a match is found, or until the Speed Sense mode is disabled by CC SF 7.
ASYNCHRONOUS EVENTS
The host either may poll the card or may be interrupt driven by the card for any asynchronous event
which can be detected by the MUX firmware. There are four major categories of events. The events
are listed below in the order of their priority.
highest priority
I
I
lowest priority
1. A break condition was received from the device
2. Any of the signal characters received
3. A data record was received from the device
4. Transmit buffer is empty
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