The hexadecimal numbers are the codes received by the printer, and the guide section helps you find a certain place in the list of codes. Each character in the guide section corresponds to one of the codes. If the code is for a printable character, that character is printed. If the code is for a non-printable character, such as ESC or the code for a line feed or carriage return, a dot is printed.

Therefore, if you run the following BASIC program while your Apex80 is in the data dump mode, you get the printout below it. The printer prints all but this last line and then stops. Press the ON/OFF LINE button to make the printer print the last line.

10

FOR X=70 TO 73

 

20

LPRINT CHR$(X): NEXT X

 

30 LPRINT CHR$(27)"E"

 

40 LPRINT

"Sample text”

 

50

LPRINT

CHR$(27)"@"

 

Data

Dump

Mode

 

 

0 0 0 0

 

4 6

OD OA 4 7 OD OA 4B 0D OA 4 9 OD 0A 1B 4 5 OD 0A

F . . G . . H . . I . . . E . .

0001

 

5 3

61 6D

7 0 6C 6 5 2 0 7 4 6 5 7 8 74 OD OA 1B 4 0 OD

Sample text. . . @.

0 0 0 2

 

0 A

 

 

 

You can consult Appendix A or the Quick Reference card to see the meaning of the hexadecimal codes. Here is an explanation of the first line to put you on the right track for using the data dump mode.

The first code in line 0000 is hex 46, which is the same as decimal 70, which is the code for "F"; therefore “F” is printed in the first position in the guide section. Then, because there is no semicolon in line 20, BASIC sends a carriage return and a line feed, hex codes 0D and 0A. Each of these is represented by a dot in the guide section. The program then sends the hex codes 47, 48, and 49, with each followed by a carriage return and line feed.

When the program gets to line 30, it sends ESC E and a carriage return and line feed. These are hex codes lB, 45, 0D, and 0A, which are represented in the guide section by a dot, an “E,” and two more dots.

Now you can follow a data dump printout on your own.

Problem Solving and Maintenance

C-5