Mitsubishi Electric MELSEC iQ-R02CPU - Length

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1 FUNCTIONS
1.3 Communications Using the Predefined Protocol
Length
The length code is used when there is an element that indicates the data length in the packet.
• When sending: Automatically calculates the data length in the specified range, and adds it to the packet.
• When receiving: From the received data, the data (value) corresponding to the length is verified as the specified range's
data length.
Length elements can be placed anywhere in the data part.
Multiple length elements can be set placed in one packet.
The following table lists the items.
*1 This can be selected only when the data length is set to 4 bytes.
Item Description Remarks
Element Name Set the element name. 
Code Type Select the data length type.
ASCII Hexadecimal/HEX

Data Length Select the data length on the line.
The range is 1 to 4 bytes.

Data Flow Forward Direction
(Upper Byte  Lower Byte)
When sending: Sends the calculated length in order from the
upper byte.
When receiving: Receives the data in order from the upper byte.
This cannot be set if the data
length is 1 byte.
Reverse Direction
(Lower Byte  Upper Byte)
When sending: Sends the calculated length in order from the low-
order byte.
When receiving: Receives the data in order from the low-order
byte.
Byte Swap (by Word)
*1
When sending: Interchanges the bytes in word units and sends the
calculated length.
When receiving: Interchanges the bytes in word units and receives
the data.
Calculating
Range
Start Select the start packet element number for the range to be calculated.
The range is 1 to 32.

End Select the end packet element number for the range to be calculated.
The range is 1 to 32.