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Serial Interface RS422
optoNCDT 1402
Data Protocol ILD1401
8.2
Setup of the Commands
8.2.1
The commands for the sensor are transmitted in full duplex mode. Each instruction has a head, the ID, the
command, the quantity and data if required (parameter, if quantity > 0).
The head contains 4 bytes to identify a connection towards the sensor. The ID consists of 2 bytes, the com-
mand and quantity) consists of 1 byte. The complete string (without parameter) has a length of 8 bytes. The
quantity is a equivalent of the subsequent bytes.
Each complete command is returned by the sensor. The answer contains the 2 ID bytes (equivalent to the
transmitted ID), the modified command byte, the quantity and response informations. The modified com-
mand byte = command OR masked with 0x80
hex
if the command was transmitted successful. If an error hap-
pens the modified command byte = command OR masked with 0xC0
hex
. In the case of an error the quantity
is 1 and contains the error code.
Byte 1
Byte 2
Byte 3
Byte 4
Byte 5
Byte 6
Byte 7
Byte 8
Byte 9
Head
ID
Command
Quantity Parameter
Set-up of a command in the transmitter
Fig. 17:
Byte 1
Byte 2
Byte 3
Byte 4
Byte 5
ID
Command OR masked with 0x80 hex
Quantity
Parameter
Set-up of a command in the receiver, error-free transmitted
Fig. 18:
Byte 1
Byte 2
Byte 3
Byte 4
Byte 5
ID
Command OR masked with 0xC0 hex
Quantity = 1 Error code
Set-up of a command in the receiver, faulty transmission
Fig. 19:
