HD9084 HDTV Caption Encoder Manual
Page 4-2 SERIAL CONTROL PROTOCOL
4.2. COMMAND SYNTAX DESCRIPTION
The Command line shows the required information in bold underlined text. Optional parameters are
shown in bold normal text. The default line shows the parameter values that will be invoked if the
optional parameter(s) are omitted. Many of the commands use control characters which are indicated
by a carat character ‘^’ preceding a letter. (E.g. Control-A is shown as ^A). Other special characters
are shown enclosed in <brackets>. (See section 4.2.1 for a description of the control characters and
special characters and their ASCII values). (All ASCII values are shown in hexadecimal notation).
Parameters are shown in lower case. (See section
4.2.2 for a description of the parameters and their
values). All upper case alphanumeric characters that are not preceded by the carat or enclosed in
brackets are to be interpreted as individual characters. (E.g. F1 is an ‘F’ followed by a ‘1’).
4.2.1. Special Characters
Most commands use control characters to communicate with the encoder. The chart below shows the
designators for the control characters and other special characters that are used in the command
descriptions: