Figure C-1 represents the ASCII character set (characters with decimal values 0 through 127). The first half of each of the numbered columns identifies the character as you would enter it on a terminal or as you would see it on a printer. Except for SP and HT, the characters with names are nonprintable. In Figure C-1, the characters with names are defined as follows:
| NUL | Null | DC1 | Device Control 1 (XON) |
| SOH | Start of Heading | DC2 | Device Control 2 |
| STX | Start of Text | DC3 | Device Control 3 (XOFF) |
| ETX | End of Text | DC4 | Device Control 4 |
| EOT | End of Transmission | NAK | Negative Acknowledge |
| ENQ | Enquiry | SYN | Synchronous Idle |
| ACK | Acknowledge | ETB | End of Transmission Block |
| BEL | Bell | CAN | Cancel |
| BS | Backspace | EM | End of Medium |
| HT | Horizontal Tab | SUB | Substitute |
| LF | Line Feed | ESC | Escape |
| VT | Vertical Tab | FS | File Separator |
| FF | Form Feed | GS | Group Separator |
| CR | Carriage Return | RS | Record Separator |
| SO | Shift Out | US | Unit Separator |
| SI | Shift In | SP | Space |
| DLE | Data Link Escape | DEL | Delete |
The remaining half of each column identifies the character by the binary value of the byte; the value is stated in three radixes- octal, decimal, and hexadecimal. For example, the uppercase letter A has, under ASCII conventions, a storage value of hexadecimal 41 (a bit configuration of 01000001), equivalent to 101 in octal notation and 65 in decimal notation.
Figure C-1 Graphic Representation of the ASCII Character Set