DEC Multinational Character Set

The data bits per character (or word length) setting of a connection plays a part in determining the allowable data which can come across that connection. More characters are displayable over an 8-bit connection than a 7-bit connection. In fact, a 1-bit difference doubles the number of allowable characters.

The increased number of allowable characters is ideal for displaying graphic characters, accents, and diacritical marks at the same time. This allows the display of multinational characters. In addition, special symbols such as a pound sign and superscripts can be displayed.

NOTE: Serial communication occurs as a serial stream of bits sent from one system to another. In order for the stream to be synchronized at both ends of the link, it is divided into frame. These frames are marked by a start bit (always 0) and a stopbit (possibly 1, 1, or 2). The data is what falls in between. In most cases, data is transmitted one byte (8 bits) at a time. However, a 7-bit word length is sometimes used for transmitting text-only files.

The DEC VT320 and VT220 emulations support the DEC Multinational Character Set which is composed of the ASCII Character Set and the DEC Supplemental Graphic set.

In this table, all characters below hex 80 make up the ASCII Character Set and all characters at and above hex 80 compose the DEC Supplemental Graphic set.

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