Computer To Terminal Data Transfers - HP 2624 Manual

configuration parameters or any other means. They are
always transmitted and your programs should include in-
put commands explicitly for accepting them. The keyboard
is disabled ("locked") until the status is sent.
Note that in either character or block line mode, the ter-
minal sends a <CR> (or8 <CR><LF> if auto line feed mode is
enabled) following the completion code; in block page mode,
it sends a block terminator character (as defined in the
Terminal Configuration menu described in section II of
this manual).
If a data comm error occurs during the transmission of the
data record, the device control completion code is un-
predictable. Data comm errors are reported by way of the
terminal status bytes described in section VIII of this
manual.
COMPUTER TO TERMINAL
DATA TRANSFERS
When either or both of the printers is selected as a destina-
tion ("to") device, you can initiate a data transfer from a
program executing in a host computer to the printer(s) by
using the following device control escape sequence:
<ESC>&p<ch8r8cter-count>W<record>
where
<character-count>
is an integer within the range 1-256
specifying the number of characters
(bytes) in
<record>.
This is an optional
parameter. If present, then the record is
terminated when the specified number
of characters have been transmitted;
otherwise the record is terminated
when the 256th data byte after the
"w"
is transmitted or by the first ASCII
<LF>
code, whichever occu rs first. If the
record is terminated by an
<LF>
the
<LD is also passed to the printer.
<record>
is the data record to be transmitted.
This escape sequence is recognized only when received over
a data comm line. It is ignored if entered through the
keyboard.
You may include the desired destination device assign-
mentes) within the escape sequence by using the "d" com-
mand parameter. You may also, prior to issuing the above
escape sequence, define the desired destination devices
either locally through the keyboard or programmatically
by way ofa separate device control «ESC>&p) sequence. In
any case, the only destination devices that are recognized
by this type of data transfer operation are the display (3d),
an external printer (4d), and/or the integral printer (6d).
If no destination devices are specified within the above
escape sequence, then the current "to" device assignments
are used. If nothing is currently selected as a "to" device,
the data record is accepted over the data comm port and
then is discarded by the terminal (also an "F" is returned as
the device control completion code.
Device Control
Binary transfers are of the form <ESC>&p<character-
count>W<record>. ASCII transfers are of the form <ESC>
&pW<record>, where an ASCII <LF> or the 256th data byte
terminates the record. In binary transfers, all eight bits
received are passed to the selected printer(s). In ASCII
transfers, the active value of the D8t8Bit
5
field in the
pertinent data communications configuration menu
determines whether seven or eight bits will be passed to the
selected printer(s).
If the escape sequence does NOT include a <ch8r8cter-
c ou n t >, then the following apply:
• IfStripNulDel=YES in the active data communications
configuration menu, the data comm firmware strips all
<NULL> and <DEL> codes from the incoming data.
• If EnqAck=YES in the active data communications
configuration menu, the data comm firmware strips all
< ENG> codes from the incoming data and responds to each
by transmitting an <ACK>.
If the escape sequence includes a <ch8r8ct er-count >, then
the following apply:
• IfEnqAck-YES in the active data communications con-
figuration menu, an <ENG> code immediately following
the
"w"
and preceding the data record is treated as part of
an Enq-Ack handshake (the data comm firmware strips
the < ENG> code from the incoming data and responds to it
by sending an <ACK».
• After the optional leading Enq-Ack handshake, ALL
characters received are treated as data (including <ENG>,
<ACK>, <NULL>, and <DEL> ) regardless ofthe setting of the
EnqAck and StripNulDel configuration fields.
When transferring a data record from the host computer to
either or both ofthe printers using the above device control
escape sequence, the remote program determines whether
or not the operation was successfully performed by execut-
ing an
I
NPUT or similar instruction that requests one
ASCII character from the terminal. The terminal responds
by sending an "S", "F", or "U". An "S" indicates successful
completion, an" F" indicates that the operation failed, and a
"u"
indicates that the terminal operator interrupted the
data transfer by pressing _ . Note that these completion
codes cannot be suppressed by configuration parameters or
any other means. They are always transmitted and your
programs should include input commands explicitly for
accepting them. The keyboard is disabled ("locked") until
the status is sent.
Note that in either character or block line mode, the ter-
minalsendsa<CR> (ora<CR> <LF> if auto line feed mode is
enabled) following the completion code; in block page mode,
it sends a block terminator character (as defined in the
Terminal Configuration menu).
If a data comm error occurs during the transmission of the
data record, the device control completion code is un-
predictable. Data comm errors are reported by way of the
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