RS-232 Prefix Byte

The RS-232 Prefix Byte Parameter Programming Mode controls the use of prefix bytes. If an RS-232 Prefix Byte is used, it is the leading character in each message sent to the host terminal. Following it is the message data. The default values are shown in the Red boxes and also in the Parameter Defaults section earlier in this chapter.

Prefix Byte

The Prefix Byte parameter contains two selections: Disable and Enable. Scan the Hex 0 tag to disable the Prefix Byte, or the Hex 1 tag to enable it.

ASCII Code

The ASCII Code parameter permits the specification of what ASCII code to use for the Prefix Byte. Enter the selection by scanning the appropriate two Hex tags (shown in the ASCII Code Chart in this chapter). Any value from 01 through 0F can be selected; however, the recommendation is to use the Start Of Text (STX) ASCII Code which is 02 Hex. Scan the two appropriate tags (Hex 0 through Hex 7 for the first character and Hex 0 through Hex F for the second).

Note:  ASCII Code parameter for the RS-232 Terminator Byte has the same function.