Chapter 7

Using the Hex Dump Feature

The SQ-2000 has the ability to print the hexadecimal number of each code that it receives, instead of interpreting the codes as characters and commands as it normally does. This is a great tool for locating problems in programs that work with the printer.

The hex dump feature is turned on by holding down both the LF and FF buttons while you turn the printer on. To turn it off simply turn the printer off and back on again.

When debugging a system, a good place to start is to attempt to print all the ASCII codes to see which ones don’t work correct- ly. If you are using BASIC the following program will do the trick:

10 FOR X=0 TO 255

20 LPRINT CHR$( X);

30 NEXT X

A perfect printout using the hex dump feature will look like Figure 7-l. Press the ON LINE button to print the last line, and remember to put the printer back on-line before you print any more.

Figure 7-1. Hex dump feature

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