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 OD and OA. 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 ESCape “E” and a carriage return and line feed. These are hex codes 1B, 45, OD, and OA, 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.

Some software changes one or more codes when sending them to the printer. The ability of the LX-90 to dump in hexadecimal lets you determine which codes are creating problems for your system.

A data dump printout of a program shows exactly what the printer is receiving, regardless of what the computer is sending. The following program run in the data dump mode can show how the computer and BASIC handle certain codes.

10 FOR X=0 TO 25520 LPRINT CHR$(X);30 NEXT X

After you type this program, put the printer in data dump mode and run the program. Remember to press the ON LINE button to make the LX-90 print the final line. Then compare your printout with the list of hex codes in order in Figure E-l.If any are skipped or repeated, you will know that your software changes some codes before it sends them to the printer.

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