Programming with Reflection

$image\rwnprg32.gif$ VTTek property

Syntax	object.VTTek object.VTTek = Value
Works with	$image\r4.gif$
Data type	Boolean

Description

When this property is set to True, Reflection supports VT340 emulation of Tektronix terminals. When this property is set to False, Reflection emulates Tektronix terminals in the same manner as Reflection for Windows 4.21 and earlier. The differences are detailed below.

Carriage Return and Line Feed Characters in bypass condition

When VTTek is set to True, a carriage return echoed from the host will clear the bypass condition and will be processed (the cursor will move to the left margin), and an immediately subsequent linefeed will also be processed. Likewise, a linefeed echoed from the host will clear the bypass condition and will be processed (the cursor will move down a line), and an immediately subsequent carriage return will also be processed.

When VTTek is set to False, a carriage return echoed from the host will clear the bypass condition, but will not be processed (the cursor doesn't move to the left margin), and an immediately subsequent linefeed will not be processed. Likewise, a linefeed echoed from the host will clear the bypass condition (the cursor doesn't move down a line), and an immediately subsequent carriage return will not be processed.

Line Feed suppression (EscLf) and Carriage Return suppression (EscCr)

When VTTek is set to True and Reflection receives an EscLf sequence, Reflection will not process any linefeeds until it receives a BEL or other no-op control code. Likewise, when VTTek is set to True and Reflection receives an EscCr sequence, Reflection will not process any carriage returns until it receives a BEL or other no-op control code.

When VTTek is set to False and Reflection receives an EscLf sequence, Reflection treats the Lf as a sequence terminator until a subsequent BEL character is received. Likewise, when VTTek is set to False and Reflection receives an EscCr sequence, Reflection treats the Cr as a sequence terminator until a subsequent BEL character is received.

Tektronix Special Point Plot Mode (EscFs)

When VTTek is set to True, Reflection treats the character following the EscFs sequence as the first character of the point address.

When VTTek is set to False, Reflection treats the character following the EscFs sequence as a gray scaling intensity character. Because Reflection does not support gray scaling, the character is ignored.

Tektronix GIN Mode Position Reports

When VTTek is set to True, Tektronix GIN mode position reports are preceded by the DECLBD down sequence. If the DECLBD sequence is null, the position report and DECLBD sequence are not sent.

When VTTek is set to False, Tektronix GIN mode position reports are not preceded by the DECLBD down sequence.

Alphanumeric Character Display

When VTTek is set to False, it's possible that alphanumeric characters may be cut off or disappear off the top of the graphics area while emulating a Tektronix terminal. If this happens, setting VTTek to True moves these characters down to the top of the graphics area.

Values

The default value is True.

$image\jump.gif$ Keyword Index

$image\popup.gif$ Related Topics

$image\popup.gif$ Reflection products that use this property