7526 DCT Reference

Advanced Features

Writing Prompts or Messages Using Cursor Control

Cursor control or positioning of the data on the display or in the display buffer is accomplished by an escape sequence embedded in the data. An ASCII escape character (hex 1B) followed by two ASCII numeric characters (01&mdash.40) positions the leftmost character of the message to be displayed at display positions 01&mdash.40.

The escape sequence may be used multiple times within a message or prompt to selectively write and skip over selected fields on the display or in the display buffer. Cursor control can be used with any message or prompt from the host command 2, B, and C or the prompt message File 8.

Example of a prompt text field with two prompts:

(DC2)(1B)04PROMPT 1(1B)19PROMPT 2(RS)

Contents of the 40-character display and display buffer with the first prompt beginning in position 4 and the second beginning in position 19.

     1   4              19                    40
   î                                            Ø
   º     PROMPT 1        PROMPT 2               º
   ü                                            à

Writing Prompts or Messages to the Display Buffer

Data written to the display times out after the interval in Timer B (File 0 download parameter) has expired. An ASCII DC2 (device control 2) character used in the first character position of the text to be displayed causes the text to be written to the display buffer. Text written to the display buffer does not time out. Text remains on the display until the display buffer is cleared by pressing the Clear key or rewriting the display buffer.

The ASCII DC2 character can be used only in the first text character position of any message being displayed. The message could come from the host through commands 2, B, and C, or it could come from the prompt message file (8) by an operator pressing a function key.

Using Autofill with Key Entry Fields

The advanced feature optional parameters available on function key definitions :2 and :3 has an autofill option. If you use the advanced features, you must specify all four parameter characters.

• In a numeric key entry field (:2), if parameter "a" has been defined as a "1," pressing the Enter key changes all unused positions of the field to zeroes.
• In an alphanumeric (:3) key entry field, if parameter "a" has been defined as a "1," pressing the Enter key changes all unused positions of the field to ASCII spaces.

Using Cursor Controls with Key Entry Fields

When you use the advanced feature optional parameters (pp) in a (:2) or (:3) function key definition, the left-most position of the field will be at (pp) 01&ndash40 display position.

Writing Key Entry Fields to the Display Buffer

The last advanced feature parameter (b) is used to write a key entry field to the display buffer. The primary use of the display buffer is to store data until another function key or badge initiated transaction sends the data to the host computer.

• When b = 0, the keyed data is displayed but not entered in the display buffer. Data written to the display times out after the interval in timer B (File 0 download parameter) has expired.
• When b = 1, the keyed data is displayed and entered into the display buffer.

If a do-not-transmit (;6) function key definition has preceded this (:2) or (:3) function key definition and you do not write the key entry field to the display buffer, the data is lost as soon as the operator presses the Enter key to complete the field.

CAUTION: