NEC NP-M311W Command Manual page 6

+-----+-----+-----+-------+-----+-----+--
| 1 | 2 | 3 | 4 | 5 | 6 |
+-----+-----+-----+---+---+-----+-----+--
| 8 | 8 | 8 | 4 | 12 | 8 |
| Bit | Bit | Bit |Bit| Bit | Bit |
+-----+-----+-----+---+---------+-----+-- ~ --+-------+--------+
| | | | |
| | | | +------------- Data length
| | | +-------------------- Model code
| | +------------------------- Projector ID
| +------------------------------- ID2
+------------------------------------- ID1
* ID1: (8 Bit)
This is an identification data assigned to each command.
Command :
This sets an identification data assigned to each command to send it.
( See each command description.)
Response :
This returns the 6th bit of received ID1 as HIGH.
For ACK it sends the 8th bit back as LOW (recognized); for NAK it
sends the 8th bit back as HIGH (not recognized).
* ID2: (8 Bit)
This is an identification data assigned to each command.
Command :
This sets an identification data assigned to each command to send it.
( See each command description.)
Response :
This returns the value of received ID2 as is.
* Projector ID : (8 Bit)
This is a projector ID for the projector that sends and receives
frames.
Command :
This specifies a projector ID for the projector that sends and
receives commands. (individual notification)
Entering 00H or FFH becomes a common command for all the projectors.
(broadcast notification)
This is convenient for controlling multiple projectors at the same
time.
* When the controller is connected with the projector on a one-to-one
basis Broadcast notification is recommended.
* When the controller is connected with multiple projectors
To control a certain projector, use "individual notification".
For all others "broadcast notification" is recommended.
Response :
This returns the projector ID for a projector received regardless of
individual notification or broadcast notification.
--+-------+--------+
~ | n | m |
--+-------+--------+
~ | 8 | 8 |
~ | Bit | Bit |