6530 Programmer's Guide

Conversational Mode Operation

2-2

6530 Programmer’s Guide

Control Codes and

Escape

Sequences

Your application program can control 6530 operation by sending control

codes and escape sequences. A control code is represented by an ASCII

character in the range of 00 to 1FH. These control codes are not

displayed or stored in memory. Instead, they invoke communications or

terminal control functions. The 6530 recognizes a subset of codes in the

control character range. See “Character Codes” on page 1-8 for details.

Escape sequences are comprised of a header, followed by a unique

instruction code, which may be followed by a required or optional

parameter. Your application program issues an escape sequence by

sending the ASCII code which represents the Esc character (1BH)

followed by the ASCII characters that represent the unique instruction

code, followed by any required or optional parameters. When the 6530

recognizes an escape code, it performs the control function associated

with that unique code. When the 6530 receives an unrecognized escape

code, it issues a command error and aborts the sequence.

Table 2-1 lists the control codes and escape sequences recognized in

conversational mode. Several other control codes used for

communications functions not listed here are described in Appendix C.

The ASCII codes for the control characters (other than the Esc character,

which is 1BH) are shown in parentheses. The control codes and escape

sequences are organized into logical groups according to function. The

following paragraphs discuss each group and control code or escape

sequence in detail.

In conversational mode, the user can also generate control codes and

escape sequences from the keyboard as described in “Keyboard

Operation” on page 1-10.

Table 2-1. Control Codes and Escape Sequences

Group

Ctrl Character

(Code) / Esc

Sequence Function

Cursor

location

DC3 (13H) Set cursor address

Esc - D Set cursor address extended

Esc a Read cursor address

Cursor

movement

Esc A Cursor up

LF (0AH) Line feed (cursor down)

Esc C Cursor right