Panasonic PT-TW381R Operating Instructions Manual page 127

Basic format (with subcommand)
Sub command (5 bytes)
*1 When transmitting a command which does not need a parameter, an operation (E) and parameter are not necessary.
Attention
f If a command is transmitted after the light source starts illuminating, there may be a delay in response or the command may not be
executed. Try sending or receiving any command after 60 seconds.
f When transmitting multiple commands, be sure to wait until 0.5 seconds has elapsed after receiving the response from the projector before
sending the next command. When transmitting a command which does not need a parameter, a colon (:) is not necessary.
Note
f If a command cannot be executed, the "ER401" response is sent from the projector to the computer.
f If an invalid parameter is sent, the "ER402" response is sent from the projector to the computer.
f ID transmission in RS-232C supports ZZ (ALL) and 01 to 06.
f If a command is sent with a specified ID, a response will be sent to the computer only in the following cases.
g It matches the projector ID
g When [PROJECTOR ID] (x page 71) on the projector is [ALL]
f STX and ETX are character codes. STX shown in hexadecimal is 02, and ETX shown in hexadecimal is 03.
Chapter 7 Appendix - Technical Information
Same as basic format
Parameter (6 bytes)*
Symbol "+" or " - " (1 byte) and set value or adjustment
value (5 bytes)
Operation (1 byte)
"=" (Value specified using parameter is set)
ENGLISH - 127