Introduction to Data Communications
Previous	22b. ASCII - American Standard Code for Information Interchange (cont'd)	Next

Of the remaining codes used by the computer, the most important ones are:

DC1 & DC2 are used in the Xon/Xoff software handshaking to control data transfer.

Displaying ASCII codes directly to the screen

You can type in the ASCII codes directly to the screen on IBM capatible computers. You press the "ALT" key and a 3 digit number on the numeric keypad. The 3 digit number is the ASCII decimal code for the character. You must use the numeric keypad, the QWERTY numbers will NOT work.

For example, the character "A" corresponds to the ASCII decimal code 65. To access the ASCII code directly, hold down the ALT key and type in 065 on the numeric keypad. On releasing the ALT key, the letter A will appear on the screen.

Table 18-2 shows the ASCII codes according to decimal numbers and hexadecimal numbers. If a network sniffer or analyzer is used, it will show raw data in decimal or hexadecimal formats. You may have to perform a manual translation using Table 18-2.

Introduction to Data Communications
Previous	Table of Contents	Next