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This means that the character being sent is replaced by a two-character sequence consisting of control character CTL-A, which indicates a quoted data byte, followed by the character itself XORed with 40 hex. For example, if the host wants to send a request for printer status (hex value 14), it sends 01 hex-54. This method of quoting means that whenever one of the eight special characters is received, the control function is intended, regardless of whether or not the preceding character is CTL-A.