Dynapro Technologies Dynapro ET TCS, Application Developer'S Manual

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The Read Character Under Cursor command causes the TCS to identify (for the host) the
character under the cursor, in effect, allowing the host to read any character displayed on the
screen.
The uses of this command include:
•
Reading the entire screen and sending it to a printer.
•
Saving a message that is displayed on the screen, displaying a new message in the same area,
and then restoring the previous message.
•
Testing the character memory of the TCS remotely.
After receiving the Read Character Under Cursor command from the host, the TCS responds by
sending a control string to the host that identifies the character at the current position of the
cursor. The control string takes the form:
<ESC>[>3;<Pc>n
<Pc> is the decimal value of the character under the cursor. For example, if <Pc> is 43, a
plus ("+") is under the cursor.
NOTE
The report may differ from the above format if the Reporting Format command has been issued. Refer to
the Reporting Format command description in Chapter 4 for details.
A character may have been displayed in one of two ways:
•
The host can send a graphic code directly to the TCS (either as a 7- or 8-bit code or as a 7-bit
ASCII code shifted to the Extended Character Set with the Select Character Set command).
•
The host can designate a National Replacement Code (NRC) and then send a graphic code to
the TCS. The TCS uses the NRC to "translate" the graphic code into the appropriate
international character on the display.
If the character under the cursor was placed there using a National Replacement Code, the
character is reported in the form:
<ESC>[>3;<Pnrc>n
<Pnrc> is the decimal value of the graphic code that was originally sent by the host before
the code was translated for display as an international character.
(It is the responsibility of the host to ensure that the NRC in effect when this command is
sent matches the NRC used when the character was originally sent to the TCS.)
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None. (This is a remote command only.)